1 Steam Cars : Phorum
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Noisy Vaporizing Burners?
Posted by: Peter Brow (IP Logged)
Date: July 24, 2002 08:31AM
<HTML>Is it true that high-output premix vaporizing burners are inherently noisy? I have read that Stanley switched from slotted to drilled burners when they went to kerosene, to (successfully?) solve a noise problem with running kero in slotted burners. With some burners (eg Ottaway), reportedly if it isn't noisy, it isn't running well. (Needs pulse combustion effect?)
I have experimented with several vaporizing burners, none of steam car size yet, and never got any noise.
On a related note, does anybody know how many gallons per hour a 23" Ottaway will burn, and at what pressure? Ottaway's figures for BTU's per square inch of burner port and mixtube area don't match the ~3.8 to 4 gph usually quoted for 23" Stanley burners, at least not in the 23" design in his plans.
Peter</HTML>
I have experimented with several vaporizing burners, none of steam car size yet, and never got any noise.
On a related note, does anybody know how many gallons per hour a 23" Ottaway will burn, and at what pressure? Ottaway's figures for BTU's per square inch of burner port and mixtube area don't match the ~3.8 to 4 gph usually quoted for 23" Stanley burners, at least not in the 23" design in his plans.
Peter</HTML>
Re: Noisy Vaporizing Burners?
Posted by: George Nutz (IP Logged)
Date: July 24, 2002 10:40AM
<HTML>Peter,
Howard Randall was talking about an Ottaway burner yesterday at a neighbors house that was in a 10 horsepower early Stanley and that it fired at a higher rate than the Stanley burner----maybe he will give some input on this. He mentioned that the entire burner was stainless steel and that its total surface was drilled giving more area than a Stanley grate(if I remember yesterday clearly).
As far as noise I had convinced two of our local SACA members to install flared trumpets on their mixing tube entrances to cut down on the shock losses. It appeared that this reduced entrance pressure drop and allowed(on one car) 20 psi more fuel pressure before howling commenced---the howling/flame modulation could be occuring when approaching oxygen deficincy. Another car was equipped with an electric exhaust axial blower and was tested with a "U" tube manometer. Although the fan in the end of the 6"x6" exhaust duct only created 1/2" of draft turning it on noticably reduced the howling(as this person always runs wide open. in this case fuel pressure could be raised to get back to the same noise level.
George</HTML>
Howard Randall was talking about an Ottaway burner yesterday at a neighbors house that was in a 10 horsepower early Stanley and that it fired at a higher rate than the Stanley burner----maybe he will give some input on this. He mentioned that the entire burner was stainless steel and that its total surface was drilled giving more area than a Stanley grate(if I remember yesterday clearly).
As far as noise I had convinced two of our local SACA members to install flared trumpets on their mixing tube entrances to cut down on the shock losses. It appeared that this reduced entrance pressure drop and allowed(on one car) 20 psi more fuel pressure before howling commenced---the howling/flame modulation could be occuring when approaching oxygen deficincy. Another car was equipped with an electric exhaust axial blower and was tested with a "U" tube manometer. Although the fan in the end of the 6"x6" exhaust duct only created 1/2" of draft turning it on noticably reduced the howling(as this person always runs wide open. in this case fuel pressure could be raised to get back to the same noise level.
George</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Terry Williams (IP Logged)
Date: July 24, 2002 11:34AM
<HTML>Jim Tangeman built a 23" burner for Don Brown's 1916 roadster, using a whole lot of perforated ceramic bicuits, about 1.25" diameter. When first fired up, it made a wonderful howl. Bill Marsh suggested he put in very small steam jets pointed into the venturis, which he did. Worked great, with a small adjustment of pressure to the jets, the howl could be eliminated. If you weren't paying attemtion to steam pressure it would let you know, when steam pressure dropped a certain amount the howl started again. I didn't mind the moan, myself.</HTML>
Re: Noisy Vaporizing Burners?
Posted by: George Nutz (IP Logged)
Date: July 24, 2002 12:27PM
<HTML>Dave Warriner used flat discs of volcanic lava 50 years ago(before ceramics) for his pilot and worked very well. The moan isn't so bad but when it howls so very loud that it is impossible to talk to each other that is another thing. Your example of steam jet boosters in the venturis is one more finger pointing at air starvation---it must be hell to get thru all those thousands of little holes, I believe the pressure drop across the drilled grate is about 2" water/.07psi.
George</HTML>
George</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Mike Clark (IP Logged)
Date: July 24, 2002 07:18PM
<HTML>I'm a new boy in all of this but have read a lot of stuff about howling burners. There has been a suggestion that howling is something to do with fluctuations in the type of combustion leading to an oscillating flame condition - I see george Nutz mentions oxygen starvation. I doubt this.
I have a 20hp Stanley with a late type drilled 23inch burner and have fitted a pressure gauge in the line between the steam automatic and the vaporiser which tells me exactly what the burner is doing. Main fuel 50/50 unleaded/diesel, pilot fuel unleaded with modified Maxwell pilot. I always run with the fuel valve at least one turn open so the vaporiser/burner controls its own fuel flow - this is what I find:-
When I fire up from cold using pilot fuel the burner howls for a short time even with only 25psi pressure in the vaporiser.
When the main fuel supply is turned on I pump fuel to 80psi to warm up -above this pressure it howls. The howling pressure rises as the system warms up until after 8 or 10 minutes it only howls at 120psi.
On the road the vaporiser pressure comes and goes as the steam auto switches on and off but howling only occurs when the vaporiser pressure gets up to the full 120psi of the fuel line. It often burns at less than 120psi, even down to 40psi when the automatic is only part open but never howls at these low pressures except when the car has been stopped and the boiler has cooled.
Howling can always be stopped by opening the stack blower which I suppose is equivalent to the fan assisted flue or the the venturi steamjets.
Howling is also heard on other combustion devices - I have a gas fired workshop heater with vertical heat exchanger pipes located above the burner just like the Stanley fire tubes. This also howls loudly for a few minutes when first lit. Interestingly I can stop the howl by opening the lower casing beneath the burner which may increase the supply of secondary air to the burner or perhaps allows the gases another route out other than up the flue. I cannot see anything happening to the flames to indicate fluctuating combustion changes.
A woodburning stove with a 7 inch flue also pulses at low frequency if I part close the door when lighting it. This stops as soon as the chimney warms up.
I watched a friend fire up his propane gas fired model steamboat with a single pass large flue leading to the funnel - it howled - more of a whistle really.
All of this convinces me that howling is an accoustic effect like blowing across the top of a bottle. I doubt it is something chemical going on in the flame as it happens with all these different fuels.
I think it occurs when the burner is trying to push gases up the flue/firetubes faster than the natural draft can take it away but my observation about letting more air into my workshop heater and the comments on flared venturis and venturi steam jets shoving more air in
do suggest the possibility that air starvation at the burner end is responsible. The considerable influence of boiler/flue temperature on howling however makes me think that it is mainly to do with the flue draft not the air supply.
Has anybody heard howling from a burner fired up in the open away from the boiler, fire tubes and flue? IF THAT HAPPENED I WOULD HAVE TO EAT MY HAT!
Terrific web site John.
Mike Clark</HTML>
I have a 20hp Stanley with a late type drilled 23inch burner and have fitted a pressure gauge in the line between the steam automatic and the vaporiser which tells me exactly what the burner is doing. Main fuel 50/50 unleaded/diesel, pilot fuel unleaded with modified Maxwell pilot. I always run with the fuel valve at least one turn open so the vaporiser/burner controls its own fuel flow - this is what I find:-
When I fire up from cold using pilot fuel the burner howls for a short time even with only 25psi pressure in the vaporiser.
When the main fuel supply is turned on I pump fuel to 80psi to warm up -above this pressure it howls. The howling pressure rises as the system warms up until after 8 or 10 minutes it only howls at 120psi.
On the road the vaporiser pressure comes and goes as the steam auto switches on and off but howling only occurs when the vaporiser pressure gets up to the full 120psi of the fuel line. It often burns at less than 120psi, even down to 40psi when the automatic is only part open but never howls at these low pressures except when the car has been stopped and the boiler has cooled.
Howling can always be stopped by opening the stack blower which I suppose is equivalent to the fan assisted flue or the the venturi steamjets.
Howling is also heard on other combustion devices - I have a gas fired workshop heater with vertical heat exchanger pipes located above the burner just like the Stanley fire tubes. This also howls loudly for a few minutes when first lit. Interestingly I can stop the howl by opening the lower casing beneath the burner which may increase the supply of secondary air to the burner or perhaps allows the gases another route out other than up the flue. I cannot see anything happening to the flames to indicate fluctuating combustion changes.
A woodburning stove with a 7 inch flue also pulses at low frequency if I part close the door when lighting it. This stops as soon as the chimney warms up.
I watched a friend fire up his propane gas fired model steamboat with a single pass large flue leading to the funnel - it howled - more of a whistle really.
All of this convinces me that howling is an accoustic effect like blowing across the top of a bottle. I doubt it is something chemical going on in the flame as it happens with all these different fuels.
I think it occurs when the burner is trying to push gases up the flue/firetubes faster than the natural draft can take it away but my observation about letting more air into my workshop heater and the comments on flared venturis and venturi steam jets shoving more air in
do suggest the possibility that air starvation at the burner end is responsible. The considerable influence of boiler/flue temperature on howling however makes me think that it is mainly to do with the flue draft not the air supply.
Has anybody heard howling from a burner fired up in the open away from the boiler, fire tubes and flue? IF THAT HAPPENED I WOULD HAVE TO EAT MY HAT!
Terrific web site John.
Mike Clark</HTML>
Re: Noisy Vaporizing Burners?
Posted by: George Nutz (IP Logged)
Date: July 24, 2002 09:14PM
<HTML>Mike,
Yes isn't this a most wonderful website for us all!!
Most of what you mention falls in line with the air starvation/pulsating flame
theory. When you start up cold and howl at 25psi it may be because the fuel is cold and the velocity of fuel coming out of the jets is very low, the ability to draw air in the mixing tubes is sort of the square of the fuel velocity that has greater momentum to drag air along with it the faster its velocity, plus the cold boiler offers no flue draft. After the 25psi period the vaporisor has heated up some and fuel pressure can be increased to 80 psi as the velocity and kinetic energy of the fuel coming out of the jets has greatly increased as well as the "stack" temperature. When things get really going 120psi is no problem---I know people that will run 200psi to really get the car rolling, howling like crazy but after everything is really hot, the kinetic energy of the fuel leaving the jets is really at a high velocity. The car I mentioned with the electric exhaust draft fan is owned by someone that has many Stanleys and has run many tests.
He mentioned a few years ago, after buying his first condensing car, that even with just a light bare chassis it would not burn as much fuel or perform as well as the earlier non-condensing cars. The earlier cars had the mixing tubes facing forward and at 45 mph would be receiving a ram effect of about 1" water pressure head, at 60mph this ram effect would be 2" of water pressure!!(Ram pressure head is a function of the velocity squared). On his condensing car the mixing tubes were about 120 degrees from the front and the ram effect was not available.
I may well be wrong in this theory but it all fits in to how much air pressure is developed heading to the grate. A few decades ago a physicist wrote a very technical paper on it and believe it was in SACA, I remember little of it as most of it was over my head, maybe someone could dig up that theoretical treatise for us to go over.
Best, George</HTML>
Yes isn't this a most wonderful website for us all!!
Most of what you mention falls in line with the air starvation/pulsating flame
theory. When you start up cold and howl at 25psi it may be because the fuel is cold and the velocity of fuel coming out of the jets is very low, the ability to draw air in the mixing tubes is sort of the square of the fuel velocity that has greater momentum to drag air along with it the faster its velocity, plus the cold boiler offers no flue draft. After the 25psi period the vaporisor has heated up some and fuel pressure can be increased to 80 psi as the velocity and kinetic energy of the fuel coming out of the jets has greatly increased as well as the "stack" temperature. When things get really going 120psi is no problem---I know people that will run 200psi to really get the car rolling, howling like crazy but after everything is really hot, the kinetic energy of the fuel leaving the jets is really at a high velocity. The car I mentioned with the electric exhaust draft fan is owned by someone that has many Stanleys and has run many tests.
He mentioned a few years ago, after buying his first condensing car, that even with just a light bare chassis it would not burn as much fuel or perform as well as the earlier non-condensing cars. The earlier cars had the mixing tubes facing forward and at 45 mph would be receiving a ram effect of about 1" water pressure head, at 60mph this ram effect would be 2" of water pressure!!(Ram pressure head is a function of the velocity squared). On his condensing car the mixing tubes were about 120 degrees from the front and the ram effect was not available.
I may well be wrong in this theory but it all fits in to how much air pressure is developed heading to the grate. A few decades ago a physicist wrote a very technical paper on it and believe it was in SACA, I remember little of it as most of it was over my head, maybe someone could dig up that theoretical treatise for us to go over.
Best, George</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Jeff Theobald (IP Logged)
Date: July 24, 2002 09:14PM
<HTML> The burner on my Brooks is fitted with a drilled cast plate, the burner howl's with a low pitch note when first started, as the temperature rises the pitch of the note increases, occasionally, seeming to jump an octave, at times the sound is unpleasant, but by the time full pressure is reached and we are ready to move off, it will normally only howl for a moment on refiring, out on the road, when the burner is running well and making good steam it will make a pleasant warbling sound, that always makes Pauline comment that the car is happy and singing.
In the Serpollet the burner is slotted and it howl's and scream's all the time, not a bad thing when you are doing a demonstration as it always keeps people back away from the car, again the burner when first lit gives a very low note, which climbs in frequencey as it warms up, sounding like a jet engine slowly winding up, again occasionally jumping an octave.
Myself I have noted that the smaller the combustion box area the more likely, and louder the howling will be, changing the jet size will change things, bigger jets= more noise, and better steaming, I think what is happening is, if complete combustion has not occured in the fire box then unburnt vapor will flash off in the tubes producing a sound, and giving better heat transfer, which would explain why the cars go so much better if howling a little, Jeff.</HTML>
In the Serpollet the burner is slotted and it howl's and scream's all the time, not a bad thing when you are doing a demonstration as it always keeps people back away from the car, again the burner when first lit gives a very low note, which climbs in frequencey as it warms up, sounding like a jet engine slowly winding up, again occasionally jumping an octave.
Myself I have noted that the smaller the combustion box area the more likely, and louder the howling will be, changing the jet size will change things, bigger jets= more noise, and better steaming, I think what is happening is, if complete combustion has not occured in the fire box then unburnt vapor will flash off in the tubes producing a sound, and giving better heat transfer, which would explain why the cars go so much better if howling a little, Jeff.</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Peter Brow (IP Logged)
Date: July 25, 2002 06:08AM
<HTML>Hi George,
This string has generated a huge amount of fascinating information! I am going to try to reply to each post, as I can't keep it all straight without being able to scroll up to what I am commenting on.
Yes, the Ottaway does have more grate opening area than the Stanley, as does the Baker. Here is where the outrageous disorganization of my 1000s of pages of invention notebooks (mostly steam stuff) drives me up the wall. Somewhere, sometime, I did a complete analysis of mixtubes, jets, plate openings, and reported firing levels for all of these, organized in a table for reference and comparison. I will see if I can find it and post it here.
However, I got the impression from the Ottaway plans that these also run on lower fuel pressure (75-85 recommended) than a stock Stanley fuel system. Then again, leave it to steamerites to boost fuel pressure way above that, no problem as the burners are much more rugged than necessary.
The Ottaway plans do describe these burners as the hottest ever designed; if true, this would indicate better than stock performance. Alas, no firing rate figures are provided.
Interesting on the air inlet trumpets. Some early photos of vaporizing burners seem to show this. Duly noted. Maybe the problem is indeed air deficiency, at least in part. Steamerites seem to love "hot rodding" their steamers -- never enough fire or steam -- and this may lead to more howling than the cars had leaving the factory. Since howling is associated with better performance, it becomes enjoyable.
Peter</HTML>
This string has generated a huge amount of fascinating information! I am going to try to reply to each post, as I can't keep it all straight without being able to scroll up to what I am commenting on.
Yes, the Ottaway does have more grate opening area than the Stanley, as does the Baker. Here is where the outrageous disorganization of my 1000s of pages of invention notebooks (mostly steam stuff) drives me up the wall. Somewhere, sometime, I did a complete analysis of mixtubes, jets, plate openings, and reported firing levels for all of these, organized in a table for reference and comparison. I will see if I can find it and post it here.
However, I got the impression from the Ottaway plans that these also run on lower fuel pressure (75-85 recommended) than a stock Stanley fuel system. Then again, leave it to steamerites to boost fuel pressure way above that, no problem as the burners are much more rugged than necessary.
The Ottaway plans do describe these burners as the hottest ever designed; if true, this would indicate better than stock performance. Alas, no firing rate figures are provided.
Interesting on the air inlet trumpets. Some early photos of vaporizing burners seem to show this. Duly noted. Maybe the problem is indeed air deficiency, at least in part. Steamerites seem to love "hot rodding" their steamers -- never enough fire or steam -- and this may lead to more howling than the cars had leaving the factory. Since howling is associated with better performance, it becomes enjoyable.
Peter</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Peter Brow (IP Logged)
Date: July 25, 2002 06:19AM
<HTML>Hi Terry,
Funny, just the other day I mentioned the idea of perforated ceramic disk flameholders in a private email. I have made a lot of ceramics, and it would be easy to make a mold for such disks or segments. The material is unbelievably cheap and easily fabricated, and can certainly take the heat. Everybody's always "beating me to the punch"! It is good to hear that the idea works! As George noted, D.A. Warriner used lava disks very successfully in the pilot of his burner.
Thanks for the info on the air-inlet steam jet -- a good fix if one doesn't like burner howling, but you are far from alone in enjoying the sound. I have read of steam jets in the boiler exhaust, usually installed to avoid backfiring, and wonder if the effect is the same.
Peter</HTML>
Funny, just the other day I mentioned the idea of perforated ceramic disk flameholders in a private email. I have made a lot of ceramics, and it would be easy to make a mold for such disks or segments. The material is unbelievably cheap and easily fabricated, and can certainly take the heat. Everybody's always "beating me to the punch"! It is good to hear that the idea works! As George noted, D.A. Warriner used lava disks very successfully in the pilot of his burner.
Thanks for the info on the air-inlet steam jet -- a good fix if one doesn't like burner howling, but you are far from alone in enjoying the sound. I have read of steam jets in the boiler exhaust, usually installed to avoid backfiring, and wonder if the effect is the same.
Peter</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Peter Brow (IP Logged)
Date: July 25, 2002 07:05AM
<HTML>Hi Mike,
Your comment on other kinds of burners howling reminded me of a certain gas wall heater at a rental property I own, which fires with a weird hollow rumble -- not sure whether to call it a howl -- when starting up cold. When warm, it quiets down. As with the burners you mentioned, the flame is blue and does not seem to pulse, at least not visibly, when howling. So perhaps it is an acoustic effect of some type, related to the temperature/density of the gases in the stack. Or maybe that is only part of what is going on.
Perhaps pulsation arises when cold tubes rapidly cool the gas next to them, which is then pushed aside by rising hot gas, then the next batch of gas to enter the area cools. This rising/falling gas temperature would cause a localized rising/falling gas pressure -- ie sound -- in a thin film or zone next to the tube. Once the tubes heat to a working temperature, the oscillation stops as localized cooling of the flowing gas reduces while the gas velocity speeds up. When the gas is moving fast enough, and/or tubes are hot enough, localized cool pockets cannot develop, at least not intermittently.
Adding a steam jet on air inlet or exhaust outlet, or reducing air inlet restriction, would disrupt this pulsation by increasing the gas flow velocity even before the tubes warm up. Changing gas velocities and changing gas/tube temperature differentials would also disrupt (or set up) the pulsation.
Resonance in the gas passages may also have an effect.
That being said, I do seem to recall an article in The Steam Automobile, early 1980s, about a vaporizing burner built in England which howled in open-air tests. I will look it up and see.
A mysterious phenomenon!
At any rate, it is reassuring to hear about Stanleys which only grumble a bit when warming up; the "silent Stanley" is not merely advertizing hokum.
Peter</HTML>
Your comment on other kinds of burners howling reminded me of a certain gas wall heater at a rental property I own, which fires with a weird hollow rumble -- not sure whether to call it a howl -- when starting up cold. When warm, it quiets down. As with the burners you mentioned, the flame is blue and does not seem to pulse, at least not visibly, when howling. So perhaps it is an acoustic effect of some type, related to the temperature/density of the gases in the stack. Or maybe that is only part of what is going on.
Perhaps pulsation arises when cold tubes rapidly cool the gas next to them, which is then pushed aside by rising hot gas, then the next batch of gas to enter the area cools. This rising/falling gas temperature would cause a localized rising/falling gas pressure -- ie sound -- in a thin film or zone next to the tube. Once the tubes heat to a working temperature, the oscillation stops as localized cooling of the flowing gas reduces while the gas velocity speeds up. When the gas is moving fast enough, and/or tubes are hot enough, localized cool pockets cannot develop, at least not intermittently.
Adding a steam jet on air inlet or exhaust outlet, or reducing air inlet restriction, would disrupt this pulsation by increasing the gas flow velocity even before the tubes warm up. Changing gas velocities and changing gas/tube temperature differentials would also disrupt (or set up) the pulsation.
Resonance in the gas passages may also have an effect.
That being said, I do seem to recall an article in The Steam Automobile, early 1980s, about a vaporizing burner built in England which howled in open-air tests. I will look it up and see.
A mysterious phenomenon!
At any rate, it is reassuring to hear about Stanleys which only grumble a bit when warming up; the "silent Stanley" is not merely advertizing hokum.
Peter</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Peter Brow (IP Logged)
Date: July 25, 2002 07:33AM
<HTML>Hi Jeff & All,
Unburnt mix firing in the flues? That would certainly increase the performance! And noise. I think that makes three theories on burner howl now, four if the pulsejet theory is included. Not to mention the old theory I once heard which ascribed it to the flames dancing erratically across the grate.
We now know many practical tested ways to eliminate burner howling -- thanks guys -- but as to what causes howling, I for one am now thoroughly confused. I can't remember what group (astrologers?) was referred to by the wag who said that if you ask three of them a question, you'll get four different opinions. Maybe he meant steam fans.
I got a smile out of the jet-engine Serpollet and happy singing Brooks. Cars do seem to have personalities, older cars more so, and steam cars most of all.
And not just personality, but deep occult mystery, especially regarding the strange workings of vaporizing burners.
Peter</HTML>
Unburnt mix firing in the flues? That would certainly increase the performance! And noise. I think that makes three theories on burner howl now, four if the pulsejet theory is included. Not to mention the old theory I once heard which ascribed it to the flames dancing erratically across the grate.
We now know many practical tested ways to eliminate burner howling -- thanks guys -- but as to what causes howling, I for one am now thoroughly confused. I can't remember what group (astrologers?) was referred to by the wag who said that if you ask three of them a question, you'll get four different opinions. Maybe he meant steam fans.
I got a smile out of the jet-engine Serpollet and happy singing Brooks. Cars do seem to have personalities, older cars more so, and steam cars most of all.
And not just personality, but deep occult mystery, especially regarding the strange workings of vaporizing burners.
Peter</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Jeff Theobald (IP Logged)
Date: July 25, 2002 08:47PM
<HTML>Hi Peter,
Further to my comments yesterday, in the Serpollet, to keep things simple, the fuel system is a large pressure tank filled with opprox 8 galls of fuel, and then pressurised to 85 psi, it will run for a day on one fill with the pressure slowly dropping to around 40 psi after about 5 to 6 hours use, the burner howl's all the time, so in that burner pressure does not seem to be relavent.
I have tested numurus burners on the workshop floor, from 14" Locomobile's to 26" 30 HP Stanley's and have never had one make any sound other than the roar of the fire.
On the Brooks I have a flue blower, and two steam jets aimed up the venturi's, the flue blower I use to stop blow backs when stopping after a run, or in traffic, the control valve only needs to be cracked, if it is turned on to much, it will pull the pilot flame out, this blower will influence the burner howl, but not much, the venturi steam jets are used to blow out an escaping fire, I have never tried to see if it changes any howling, we are out in the Brooks this weekend so I will see what changes it makes.
The reference to jet engine's comes from an interest in small gas turbine's, I have one or two and keep one ready to run, it's a real buzz standing alongside an engine as it starts up and runs, all the best, Jeff.</HTML>
Further to my comments yesterday, in the Serpollet, to keep things simple, the fuel system is a large pressure tank filled with opprox 8 galls of fuel, and then pressurised to 85 psi, it will run for a day on one fill with the pressure slowly dropping to around 40 psi after about 5 to 6 hours use, the burner howl's all the time, so in that burner pressure does not seem to be relavent.
I have tested numurus burners on the workshop floor, from 14" Locomobile's to 26" 30 HP Stanley's and have never had one make any sound other than the roar of the fire.
On the Brooks I have a flue blower, and two steam jets aimed up the venturi's, the flue blower I use to stop blow backs when stopping after a run, or in traffic, the control valve only needs to be cracked, if it is turned on to much, it will pull the pilot flame out, this blower will influence the burner howl, but not much, the venturi steam jets are used to blow out an escaping fire, I have never tried to see if it changes any howling, we are out in the Brooks this weekend so I will see what changes it makes.
The reference to jet engine's comes from an interest in small gas turbine's, I have one or two and keep one ready to run, it's a real buzz standing alongside an engine as it starts up and runs, all the best, Jeff.</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Peter Brow (IP Logged)
Date: July 26, 2002 09:12AM
<HTML>Hi Jeff,
Well, maybe it is the combustion chamber size (as installed in boiler). I have never gotten any howling out of the small vaporizing burners I have run, and none were installed in a boiler. I have read of some Stanley owners using deeper-than-stock combustion chambers with a stock firing rate; perhaps for cleaner or quieter burning?
Those small jet turbines are a blast. I read recently that TV show host Jay Leno (also a steam car owner) has a motorcycle powered by a small jet helicopter engine. Fuel mileage is horrible, but performance is quite hairy. Its builder also offers custom jet-powered pickup trucks!
Peter</HTML>
Well, maybe it is the combustion chamber size (as installed in boiler). I have never gotten any howling out of the small vaporizing burners I have run, and none were installed in a boiler. I have read of some Stanley owners using deeper-than-stock combustion chambers with a stock firing rate; perhaps for cleaner or quieter burning?
Those small jet turbines are a blast. I read recently that TV show host Jay Leno (also a steam car owner) has a motorcycle powered by a small jet helicopter engine. Fuel mileage is horrible, but performance is quite hairy. Its builder also offers custom jet-powered pickup trucks!
Peter</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Rolly Evans (IP Logged)
Date: July 26, 2002 09:32AM
<HTML>My combustion chamber is deeper then stock. I added a three in ring just under the boiler with a locking flange to alien the burner pan. I don’t have to reseal each time I drop the pan. I drilled the burner out to 6000 holes. Total burn area is 15-1/4 sq inches. Even with trumpet ends I still get some howling. I kind of like to hear a little noise, its not really loud but I know when it relights.</HTML>
Re: Noisy Vaporizing Burners?
Posted by: David K. Nergaard (IP Logged)
Date: July 26, 2002 11:24AM
<HTML>For what it is worth, my Stanley burner howls if it is forced regardless of whether it is under a boiler. It is quieter under the boiler, I guess because the noise has to work to get out.
It is a drilled type, originally having nearly 8000 holes #56 drill size. It steamed very well and howled only when cool, even with 160 psi. fuel pressurel. After more than twenty years of use, often with weepy boilers, many of the holes had rusted up. I drilled them out #54 drill. BIG MISTAKE! The thing howled horribly at fuel pressures more than 30 psi. I plugged enough holes to make it similar to a stock Stanley, ~4500 holes. Now it can be used at 140 psi. without too much noise, but does not steam as well as before.
I ran a series of tests to see what nozzle size allowed the greatest fuel flow without howling. I got the best results with drill size #62, just what Stanley stated in their instruction books for the 20 hp. burner. The tests were done with the buner on the ground in front of the car, these things will howl in the open!</HTML>
It is a drilled type, originally having nearly 8000 holes #56 drill size. It steamed very well and howled only when cool, even with 160 psi. fuel pressurel. After more than twenty years of use, often with weepy boilers, many of the holes had rusted up. I drilled them out #54 drill. BIG MISTAKE! The thing howled horribly at fuel pressures more than 30 psi. I plugged enough holes to make it similar to a stock Stanley, ~4500 holes. Now it can be used at 140 psi. without too much noise, but does not steam as well as before.
I ran a series of tests to see what nozzle size allowed the greatest fuel flow without howling. I got the best results with drill size #62, just what Stanley stated in their instruction books for the 20 hp. burner. The tests were done with the buner on the ground in front of the car, these things will howl in the open!</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Alan Woolf (IP Logged)
Date: July 27, 2002 12:38AM
<HTML>George,
Could you be a more specific about the shape of flared trumpets that you prescribed to reduce the howl?
Our 1917 Stanley with a 23" drilled Stanley type burner (fabrciated by John Goold and I think has 5000+ holes) and is very loud when running much above 1/4 turn on the main fuel valve. We are running #58 jets at 160 psi. The car really seems to fire better when I can keep it just at the point where is almost howling. I don't really like the howling. I think a Stanley should be quiet. We have tried various combinations of jets and fuel pressures without good results. Usually eliminating the howl kills the performance. We have also experimented with stepped jets in attempt to change the pressure ratio without a lot of success.
Any other ideas how to quiet down a noisy burner would be appreciated.
Alan</HTML>
Could you be a more specific about the shape of flared trumpets that you prescribed to reduce the howl?
Our 1917 Stanley with a 23" drilled Stanley type burner (fabrciated by John Goold and I think has 5000+ holes) and is very loud when running much above 1/4 turn on the main fuel valve. We are running #58 jets at 160 psi. The car really seems to fire better when I can keep it just at the point where is almost howling. I don't really like the howling. I think a Stanley should be quiet. We have tried various combinations of jets and fuel pressures without good results. Usually eliminating the howl kills the performance. We have also experimented with stepped jets in attempt to change the pressure ratio without a lot of success.
Any other ideas how to quiet down a noisy burner would be appreciated.
Alan</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Mike Clark (IP Logged)
Date: July 29, 2002 08:08PM
<HTML>Alan, George, David and all!
David - I ate the hat! I really didn't think a bare burner would howl on it's own without the boiler and flues. I just tried to emulate the howl with a gas torch firing up a half inch pipe - it just roars if you push it to within a quarter inch but no howl.
When you think about it even if the tubes do have some accoustic effect there has to be something to create a vibration - after all a clarinet has a reed.
I re-read a piece by U.H. Shaw in Light Steam Power for Jan 1965. He says howling is due to an oscillation caused by quickly alternating chemistry in the flame. He says that generally vaporising burners burn in a two stage chemistry, the paraffin first oxidising to an aldehyde then to CO2 whereas in an atomising burner the process goes direct to CO2. When a Stanley burner howls, according to this theory, the flame is unstable and switches from the slower to the quicker more direct burning process many times a second, thereby setting off vibrations and howling.
I have no idea whether this is right but could it be that when howling the the vaporiser is being pushed right to its limit and that the burner is being fed with a mixture of gas and spray. This would surely affect the burning process. It still doesn't explain why my gas workshop heater and wood burning stove howl and pulsate!
Like I said before I am new to this but have spent a year getting my H5 up to good running order. A lot of this time has gone into pilot, steam automatic and vaporiser. I think we can learn something by thinking about how the vaporiser works. I did a test to see how much fuel would go through the burner jets if no heat were applied to the vaporiser. It turns out that the automatic and the jets (#57s) would pass up to 50 gallons per hour with 120psi. It's the speed at which the expanding gas can get out through the jets which determines how much fuel actually goes through when it is fired up. Obviously the vaporiser has a limited capability of vaporising fuel, determined by its length and the heat around it. When the steam automatic is only partly open the fuel will flow through, finding its own rate of flow, being fully vaporised and forced out as gas with a vaporiser pressure below the fuel line pressure and no howl. When the automatic is fully open the fuel line pressure takes over, shoving the fuel through and possibly getting to the point where some goes through unvaporised. Perhaps this is when it howls - the combustion chemistry setting off a vibration.
The partly vaporised fuel must be able to pull enough air in weight for weight otherwise the burner and vaporiser would cool and the fuel flow turn to a horrible wet squirt just like on the old kerosene blowlamps. Maybe going to the limit of what the vaporiser can vaporise actually gets more fuel and air into the burner. I don't know whether anyone has seen whether howling is associated with incomplete vaporisation.
Alan ( I remember we met in Vermont in 92 , my first steam car visit) running with only one quarter turn on your fuel valve is holding back the supply of fuel so that it can't build up full pressure by expanding in the vaporiser, the fuel may then spend too long in the vaporiser and carbonise. I would try smaller jets and open the tap up. I run with one turn open, currently using #60 jets and the vaporiser wire stays completely clean and no carbon in jets. I tried no 62 like Stanley says but it definately lost power. Tried 57s - power not very different to no 60s but definately howled more. I'll try something in between. Mine is also a John Goold burner, with a six foot vaporiser.
Alan you also asked about flared trumpets. The carburettor boys know all about this - I read that to smooth the airflow into a carb it is best to have a trumpet with a radius about 1/4 inch with the flared lip about 1/2 inch wide turned slightly back on itself. I did this on an SU carb fitted to a 1925 car I have and thought I could feel a difference. The only concern I have with Stanley venturis facing forward is that the pilot seems to cool down at speeds over 45 mph.
Mike</HTML>
David - I ate the hat! I really didn't think a bare burner would howl on it's own without the boiler and flues. I just tried to emulate the howl with a gas torch firing up a half inch pipe - it just roars if you push it to within a quarter inch but no howl.
When you think about it even if the tubes do have some accoustic effect there has to be something to create a vibration - after all a clarinet has a reed.
I re-read a piece by U.H. Shaw in Light Steam Power for Jan 1965. He says howling is due to an oscillation caused by quickly alternating chemistry in the flame. He says that generally vaporising burners burn in a two stage chemistry, the paraffin first oxidising to an aldehyde then to CO2 whereas in an atomising burner the process goes direct to CO2. When a Stanley burner howls, according to this theory, the flame is unstable and switches from the slower to the quicker more direct burning process many times a second, thereby setting off vibrations and howling.
I have no idea whether this is right but could it be that when howling the the vaporiser is being pushed right to its limit and that the burner is being fed with a mixture of gas and spray. This would surely affect the burning process. It still doesn't explain why my gas workshop heater and wood burning stove howl and pulsate!
Like I said before I am new to this but have spent a year getting my H5 up to good running order. A lot of this time has gone into pilot, steam automatic and vaporiser. I think we can learn something by thinking about how the vaporiser works. I did a test to see how much fuel would go through the burner jets if no heat were applied to the vaporiser. It turns out that the automatic and the jets (#57s) would pass up to 50 gallons per hour with 120psi. It's the speed at which the expanding gas can get out through the jets which determines how much fuel actually goes through when it is fired up. Obviously the vaporiser has a limited capability of vaporising fuel, determined by its length and the heat around it. When the steam automatic is only partly open the fuel will flow through, finding its own rate of flow, being fully vaporised and forced out as gas with a vaporiser pressure below the fuel line pressure and no howl. When the automatic is fully open the fuel line pressure takes over, shoving the fuel through and possibly getting to the point where some goes through unvaporised. Perhaps this is when it howls - the combustion chemistry setting off a vibration.
The partly vaporised fuel must be able to pull enough air in weight for weight otherwise the burner and vaporiser would cool and the fuel flow turn to a horrible wet squirt just like on the old kerosene blowlamps. Maybe going to the limit of what the vaporiser can vaporise actually gets more fuel and air into the burner. I don't know whether anyone has seen whether howling is associated with incomplete vaporisation.
Alan ( I remember we met in Vermont in 92 , my first steam car visit) running with only one quarter turn on your fuel valve is holding back the supply of fuel so that it can't build up full pressure by expanding in the vaporiser, the fuel may then spend too long in the vaporiser and carbonise. I would try smaller jets and open the tap up. I run with one turn open, currently using #60 jets and the vaporiser wire stays completely clean and no carbon in jets. I tried no 62 like Stanley says but it definately lost power. Tried 57s - power not very different to no 60s but definately howled more. I'll try something in between. Mine is also a John Goold burner, with a six foot vaporiser.
Alan you also asked about flared trumpets. The carburettor boys know all about this - I read that to smooth the airflow into a carb it is best to have a trumpet with a radius about 1/4 inch with the flared lip about 1/2 inch wide turned slightly back on itself. I did this on an SU carb fitted to a 1925 car I have and thought I could feel a difference. The only concern I have with Stanley venturis facing forward is that the pilot seems to cool down at speeds over 45 mph.
Mike</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Mike Clark (IP Logged)
Date: July 30, 2002 11:32AM
<HTML>Alan,Peter, George, David, Jeff and all,
Apologies for sending more stuff before you read the last bit!
Can I clarify on how I think vaporisers, jets and steam automatic interact. To understand things its often easiest to look at the extremes of operational range.
Assume the burner is hot, the fire out and the steam auto just cracking open. The vaporiser is empty. Fuel flows in under fuel line pressure, slowly at first as the valve is only just opening. The fuel turns to gas, expanding and filling the vaporiser until gets to the jets. The valve continues to open letting in more fuel and building up pressure to the point where enough gas is escaping the jet to draw air into the mixing chamber and light the burner. If the steam demand is not particularly high the steam auto doesn't fully open and the fuel flow is a balance of what can get in under fuel line pressure through the part open steam automatic, the heat applied to the vaporiser and consequent expansion of gas, and the rate of gas escape through the jets. In this situation the gas has time to be fully vaporised before it gets to the jets and you get a quiet burn with no howling. The pressure in the vaporiser may be as low as 40psi yet firing still goes on as it should. The burner won't howl unless the vaporiser pressure gets up to the same pressure as the fuel line. The steam automatic is controlling (modulating) the rate of fuel flow.
If the steam demand is high enough the steam auto opens fully, the gas pressure in the vaporiser rises up to the fuel line pressure and then the jet size controls how much fuel goes through. If the jets are small, say #62 the pressure build up holds back the inflow of fuel so that it is slow enough that the vaporiser can always vaporise all the fuel going through. It doesn't matter how much the steam auto opens, the balance of vaporiser pressure against fuel line pressure is what determines whether fuel goes in. If the jets are bigger there is less resistance and much more fuel flows to the point where the vaporiser is no longer able to gasify all the passing fuel. When this happens I suppose some fuel must go through as a spray, mixed with the gas, presumably pulling sufficient air to burn cleanly and giving us a cross bred burner, part vaporising, part atomising. Presumably most of this unvaporised fuel will get vaporised during its passage through the mixing chamber and burner plate. It does rather suggest that shoving in unvaporised fuel may be a good way of getting more power. I know not whether this is why they howl but the evidence seems to fit the case.
The trick of making it all work is to find the right balance of vaporiser length and position in the flame, fuel line pressure and jet size. As I said before I think the main fuel valve should be kept well open - to do otherwise is to make the fuel dribble in which may stop the howl but cook the fuel. Alan mentioned running 160psi and howling with over 1/4 turn on the valve - it would be really interesting to see what vaporiser pressure gets the howl going. Alan - if you put a small pressure gauge on the spare outlet on the steam auto you will really see what is going on.
Another interesting conclusion came to me with a significant practical benefit. My test of liquid fuel flow through the jets without heat (up to 50gph) made me wonder whether it would be useful to reduce the volume of the pipe from the automatic to the vaporiser - a space which has to be filled each time the automatic opens and before the vaporiser pressure rises enough to take control of the flow. I had always felt that my burner lit up with quite a pop and thought this sudden uncontrolled rush of fuel might be the cause. I replaced the 1/4 pipe with a 3/16th pipe filled with 4 one millimetre copper wires. The cross sectional area is still about double that of the two jets but the pipe holds less than 1cc of fuel instead of 7 or 8 cc.The burner now lights very quietly and of course there is a bit less fuel to burn off when it shuts down. The full burn rate is unchanged - it still howls!
Mike</HTML>
Apologies for sending more stuff before you read the last bit!
Can I clarify on how I think vaporisers, jets and steam automatic interact. To understand things its often easiest to look at the extremes of operational range.
Assume the burner is hot, the fire out and the steam auto just cracking open. The vaporiser is empty. Fuel flows in under fuel line pressure, slowly at first as the valve is only just opening. The fuel turns to gas, expanding and filling the vaporiser until gets to the jets. The valve continues to open letting in more fuel and building up pressure to the point where enough gas is escaping the jet to draw air into the mixing chamber and light the burner. If the steam demand is not particularly high the steam auto doesn't fully open and the fuel flow is a balance of what can get in under fuel line pressure through the part open steam automatic, the heat applied to the vaporiser and consequent expansion of gas, and the rate of gas escape through the jets. In this situation the gas has time to be fully vaporised before it gets to the jets and you get a quiet burn with no howling. The pressure in the vaporiser may be as low as 40psi yet firing still goes on as it should. The burner won't howl unless the vaporiser pressure gets up to the same pressure as the fuel line. The steam automatic is controlling (modulating) the rate of fuel flow.
If the steam demand is high enough the steam auto opens fully, the gas pressure in the vaporiser rises up to the fuel line pressure and then the jet size controls how much fuel goes through. If the jets are small, say #62 the pressure build up holds back the inflow of fuel so that it is slow enough that the vaporiser can always vaporise all the fuel going through. It doesn't matter how much the steam auto opens, the balance of vaporiser pressure against fuel line pressure is what determines whether fuel goes in. If the jets are bigger there is less resistance and much more fuel flows to the point where the vaporiser is no longer able to gasify all the passing fuel. When this happens I suppose some fuel must go through as a spray, mixed with the gas, presumably pulling sufficient air to burn cleanly and giving us a cross bred burner, part vaporising, part atomising. Presumably most of this unvaporised fuel will get vaporised during its passage through the mixing chamber and burner plate. It does rather suggest that shoving in unvaporised fuel may be a good way of getting more power. I know not whether this is why they howl but the evidence seems to fit the case.
The trick of making it all work is to find the right balance of vaporiser length and position in the flame, fuel line pressure and jet size. As I said before I think the main fuel valve should be kept well open - to do otherwise is to make the fuel dribble in which may stop the howl but cook the fuel. Alan mentioned running 160psi and howling with over 1/4 turn on the valve - it would be really interesting to see what vaporiser pressure gets the howl going. Alan - if you put a small pressure gauge on the spare outlet on the steam auto you will really see what is going on.
Another interesting conclusion came to me with a significant practical benefit. My test of liquid fuel flow through the jets without heat (up to 50gph) made me wonder whether it would be useful to reduce the volume of the pipe from the automatic to the vaporiser - a space which has to be filled each time the automatic opens and before the vaporiser pressure rises enough to take control of the flow. I had always felt that my burner lit up with quite a pop and thought this sudden uncontrolled rush of fuel might be the cause. I replaced the 1/4 pipe with a 3/16th pipe filled with 4 one millimetre copper wires. The cross sectional area is still about double that of the two jets but the pipe holds less than 1cc of fuel instead of 7 or 8 cc.The burner now lights very quietly and of course there is a bit less fuel to burn off when it shuts down. The full burn rate is unchanged - it still howls!
Mike</HTML>
Re: Noisy Vaporizing Burners?
Posted by: David K. Nergaard (IP Logged)
Date: July 30, 2002 01:10PM
<HTML>It is easy to tell whether the fuel is fully vaporized with a Stanley burner: if you can see the fuel from the jets going into the mixing tubes, it is not. The visible portion is liquid drpplets.
For that matter ALL burners are vaporizing burners. Liquid fuel won't burn. The difference is whether one vaporizes the fuel outside the fire, as with a Stanley, or IN the fire, as with all gun type burners. Vaporizing the fuel and mixing it with the needed air outside the fire gives very rapid combustion which allows a very compact flame space. Flame length measured in inches rather than feet.</HTML>
For that matter ALL burners are vaporizing burners. Liquid fuel won't burn. The difference is whether one vaporizes the fuel outside the fire, as with a Stanley, or IN the fire, as with all gun type burners. Vaporizing the fuel and mixing it with the needed air outside the fire gives very rapid combustion which allows a very compact flame space. Flame length measured in inches rather than feet.</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Peter Brow (IP Logged)
Date: July 31, 2002 07:04AM
<HTML>Hi David and Mike,
Fascinating comments! Somewhere here in Stanleysteamers.com is an excellent photo of a coffin-nose Stanley burner (tubes facing forward; shot from front of car) with clearly visible cones of white fuel vapor/mist(?) exiting the jets. I never saw white cones in my (no-noise) "v-burner" experiments.
Perhaps full vaporization at maximum firing would require too long a vaporizer, resulting in excess carbon formation at low firing rates. If so, these vaporizer lengths would tend to be tried, abandoned, and advised against. Therefore vaporizers/jets in higher-performance burners would tend to end up sized for some liquid spray/howling at high firing rates?
I don't know if unvaporized fuel is a cause of howling or not, but I have noticed that the vaporizers in the (noisy at full fire) Ottaway plans have less heating area than stock Stanley vaporizers.
Mike: congratulations on your ingenious modification to give quieter burner lighting and quicker shutoff, and on the idea of adding a gauge at the steam automatic output to measure vaporizer fuel pressure. I now plan to try both of these ideas.
Is it possible that vaporizer pressure in some burners/control systems may actually pulse slightly _higher_ than fuel pressure, thus causing a pulsation in fuel flow which feeds through to the firebox? I seem to recall reading about a special Bunsen burner called the "singing flame", in which low-volume audible sound waves introduced upline from the flame were amplified by the flame itself.
David: Good comments on the advantages of premix vaporizing burners. I like the absence of a fan, control entirely by valve modulation, standby pilot potential, and general simplicity. I wonder how the latest Coleman burners are able to handle today's horrible automotive gasoline without excessive carbon buildup or goo drooling from jets? Users of the new type have told me that the generators (vaporizers) don't have to be replaced more often than those designed for white gas. I think I will buy one myself and do some tests and measurements.
Peter</HTML>
Fascinating comments! Somewhere here in Stanleysteamers.com is an excellent photo of a coffin-nose Stanley burner (tubes facing forward; shot from front of car) with clearly visible cones of white fuel vapor/mist(?) exiting the jets. I never saw white cones in my (no-noise) "v-burner" experiments.
Perhaps full vaporization at maximum firing would require too long a vaporizer, resulting in excess carbon formation at low firing rates. If so, these vaporizer lengths would tend to be tried, abandoned, and advised against. Therefore vaporizers/jets in higher-performance burners would tend to end up sized for some liquid spray/howling at high firing rates?
I don't know if unvaporized fuel is a cause of howling or not, but I have noticed that the vaporizers in the (noisy at full fire) Ottaway plans have less heating area than stock Stanley vaporizers.
Mike: congratulations on your ingenious modification to give quieter burner lighting and quicker shutoff, and on the idea of adding a gauge at the steam automatic output to measure vaporizer fuel pressure. I now plan to try both of these ideas.
Is it possible that vaporizer pressure in some burners/control systems may actually pulse slightly _higher_ than fuel pressure, thus causing a pulsation in fuel flow which feeds through to the firebox? I seem to recall reading about a special Bunsen burner called the "singing flame", in which low-volume audible sound waves introduced upline from the flame were amplified by the flame itself.
David: Good comments on the advantages of premix vaporizing burners. I like the absence of a fan, control entirely by valve modulation, standby pilot potential, and general simplicity. I wonder how the latest Coleman burners are able to handle today's horrible automotive gasoline without excessive carbon buildup or goo drooling from jets? Users of the new type have told me that the generators (vaporizers) don't have to be replaced more often than those designed for white gas. I think I will buy one myself and do some tests and measurements.
Peter</HTML>
Re: Visible Fuel Vapor Cones
Posted by: Peter Brow (IP Logged)
Date: July 31, 2002 07:24AM
<HTML>Click here to see a photo beautifully illustrating the visible fuel flow which David mentioned:
[www.stanleysteamers.com]
This has got to be my favorite steam car "action photo" of all time!
Peter</HTML>
[www.stanleysteamers.com]
This has got to be my favorite steam car "action photo" of all time!
Peter</HTML>
Re: Visible Fuel Vapor Cones
Posted by: Jim Crank (IP Logged)
Date: July 31, 2002 02:03PM
<HTML>Peter, et al,
I am wondering if the burner howl from the Stanley type burner is not generated strictly in the two venturi pipes? Knowing the length, I have a chart for organ pipes that gives the prime frequency for open pipes and stopped pipes. As the burner warms up and the fuel goes from milky white to invisible, the frequency goes higher. Seems as if this says the milky vapor is denser than the fully vaporized, thus the lower frequency.
I wonder if anyone has an audio frequency meter, the kind with a microphone? Measure the real frequency and let me look up the prime on the tables. Such a meter was sometimes available in hobby shops as an audio tachometer for model airplane engines.
My White when really pushed hard when cold would scream, high pitched and very loud. My old Stanley with a 3" venturi burner would yodel, jumped up and down what sounded like one octave. Everyone thought it very funny.
Jim</HTML>
I am wondering if the burner howl from the Stanley type burner is not generated strictly in the two venturi pipes? Knowing the length, I have a chart for organ pipes that gives the prime frequency for open pipes and stopped pipes. As the burner warms up and the fuel goes from milky white to invisible, the frequency goes higher. Seems as if this says the milky vapor is denser than the fully vaporized, thus the lower frequency.
I wonder if anyone has an audio frequency meter, the kind with a microphone? Measure the real frequency and let me look up the prime on the tables. Such a meter was sometimes available in hobby shops as an audio tachometer for model airplane engines.
My White when really pushed hard when cold would scream, high pitched and very loud. My old Stanley with a 3" venturi burner would yodel, jumped up and down what sounded like one octave. Everyone thought it very funny.
Jim</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Ray Woolf (IP Logged)
Date: July 31, 2002 05:23PM
<HTML>In my opinion, the noise from the Stanley burners comes from the fuel
going supersonic when it emerges from the jets. The shock waves set up
a vibration in the mixing tubes and from that comes the sound. If one takes a mixing tube, not in a burner but on the bench, and passes a stream of air across the end of the mixing tube, a howling noise, similar to
the noise when a burner is being fired, results. I say 'similar' because the
sound is insulated, somewhat, by the surrounding burner.
If one lowers the fuel pressure enough to maintain a subsonic stream
emerging from the jets, the velocity of the jetstream is too low to entrain
enough air to completely burn the fuel and it will smoke abundantly. Perhaps, it would be possible to use a steam jet in each mixing tube to
overcome this difficulty.</HTML>
going supersonic when it emerges from the jets. The shock waves set up
a vibration in the mixing tubes and from that comes the sound. If one takes a mixing tube, not in a burner but on the bench, and passes a stream of air across the end of the mixing tube, a howling noise, similar to
the noise when a burner is being fired, results. I say 'similar' because the
sound is insulated, somewhat, by the surrounding burner.
If one lowers the fuel pressure enough to maintain a subsonic stream
emerging from the jets, the velocity of the jetstream is too low to entrain
enough air to completely burn the fuel and it will smoke abundantly. Perhaps, it would be possible to use a steam jet in each mixing tube to
overcome this difficulty.</HTML>
Noisy vaporising burners
Posted by: Mike Clark (IP Logged)
Date: July 31, 2002 05:29PM
<HTML>Peter
I like your suggestion that vaporiser pressure oscillation above and below fuel line pressure is the prime source of vibration in a howling burmer. This would be very likely in the perhaps slightly unstable conditions of part vaporisation at full fire. At lower output, when the limiting factor is the valve opening in the steam automatic, I think the flow of fuel in and gas out would be a very steady process hence no howl.
When I first turn on my main burner to start up on pilot fuel my vaporiser pressure gauge does show a higher pressure than the pilot fuel line. I've not noticed this much since bumping my pilot up to 40psi but earlier when using 25psi I would see pressures up to 35-40 psi on the gauge for a moment, just as the main burner started to light and a vaporiser load of pilot fuel got pushed through to the preheated hot part above the pilot light. It dropped back to pilot line pressure after a few seconds, presumably as the burst of pressure stopped fuel going in. I can imagine something similar happening continuously when the burner gets howling on full power. We would need some modern instrumentation to prove this. We still wouldn't know if the noise originated in the flame or as Jim suggests in the venturis.
Jim - the above is absolutely compatible with your view of resonating frequency in the venturi pipes - they are the trumpet , the vaporiser is Louis Armstrong!
When I tried a loop pilot with unleaded fuel (see new thread on Maxwell and Coleman things) I had a lot of problems with uneven vaporisation and a pulsating flame - this was slow enough that I could feel the heat surging back and forth in the pilot fuel supply pipe a couple of inches back from the pilot itself. I changed the pipe from 3/16 to 1/8inch and this pretty well stopped it. Les Nelson had a check valve in his pilot feed pipe for the same reason. I think this surge was due to the lighter fractions of the unleaded fuel vaporising uncontrollably and pushing the fuel back up the pipe, stopping the supply and killing the surge. Perhaps something similar happens in the main burner but at a higher frequency.
David - I know you can see poor vaporisation but so far I have never remembered to look at the critical moment when the howling starts. I generally try not to howl when standing in the yard as it annoys my wife!
Mike</HTML>
I like your suggestion that vaporiser pressure oscillation above and below fuel line pressure is the prime source of vibration in a howling burmer. This would be very likely in the perhaps slightly unstable conditions of part vaporisation at full fire. At lower output, when the limiting factor is the valve opening in the steam automatic, I think the flow of fuel in and gas out would be a very steady process hence no howl.
When I first turn on my main burner to start up on pilot fuel my vaporiser pressure gauge does show a higher pressure than the pilot fuel line. I've not noticed this much since bumping my pilot up to 40psi but earlier when using 25psi I would see pressures up to 35-40 psi on the gauge for a moment, just as the main burner started to light and a vaporiser load of pilot fuel got pushed through to the preheated hot part above the pilot light. It dropped back to pilot line pressure after a few seconds, presumably as the burst of pressure stopped fuel going in. I can imagine something similar happening continuously when the burner gets howling on full power. We would need some modern instrumentation to prove this. We still wouldn't know if the noise originated in the flame or as Jim suggests in the venturis.
Jim - the above is absolutely compatible with your view of resonating frequency in the venturi pipes - they are the trumpet , the vaporiser is Louis Armstrong!
When I tried a loop pilot with unleaded fuel (see new thread on Maxwell and Coleman things) I had a lot of problems with uneven vaporisation and a pulsating flame - this was slow enough that I could feel the heat surging back and forth in the pilot fuel supply pipe a couple of inches back from the pilot itself. I changed the pipe from 3/16 to 1/8inch and this pretty well stopped it. Les Nelson had a check valve in his pilot feed pipe for the same reason. I think this surge was due to the lighter fractions of the unleaded fuel vaporising uncontrollably and pushing the fuel back up the pipe, stopping the supply and killing the surge. Perhaps something similar happens in the main burner but at a higher frequency.
David - I know you can see poor vaporisation but so far I have never remembered to look at the critical moment when the howling starts. I generally try not to howl when standing in the yard as it annoys my wife!
Mike</HTML>
Re: Visible Fuel Vapor Cones
Posted by: George Nutz (IP Logged)
Date: July 31, 2002 06:51PM
<HTML>Ray, Mike & Jim,
If that paper done by the physicist long ago on the causes of Stanley burner howling could be found we would have more insight. I do believe the mixing tubes are partially responsible for the "frequency of howl " but if the mixing tubes are the trumpet and the vaporizor Lous or Bix ;0) then the grate is the resistance to output, much like a trumpet mute. The one thing I will always reconsider is that if steam jet or electric exhaust draft boosters on the exhaust side of the grate diminish or stop howling(they would actually increase total flue gas flow) and if the two little trumpet inlet experiments, that reduce shock losses to the venturies, reduce howling than the frequency and decibel level do not seem predominantly dependent upon the mixing tube diameter and length. Just more hot air for thought.
Best, George</HTML>
If that paper done by the physicist long ago on the causes of Stanley burner howling could be found we would have more insight. I do believe the mixing tubes are partially responsible for the "frequency of howl " but if the mixing tubes are the trumpet and the vaporizor Lous or Bix ;0) then the grate is the resistance to output, much like a trumpet mute. The one thing I will always reconsider is that if steam jet or electric exhaust draft boosters on the exhaust side of the grate diminish or stop howling(they would actually increase total flue gas flow) and if the two little trumpet inlet experiments, that reduce shock losses to the venturies, reduce howling than the frequency and decibel level do not seem predominantly dependent upon the mixing tube diameter and length. Just more hot air for thought.
Best, George</HTML>
Re: Visible Fuel Vapor Cones
Posted by: Peter Brow (IP Logged)
Date: August 01, 2002 08:59AM
<HTML>Ray, Mike, Jim, George, and Everyone:
Sounds like all these factors -- vaporizer, jets, mixtubes, grate, combustion chamber size, and flue -- have an impact on vaporizing burner noise. Fuel & combustion chemistry probably also play roles; Stanley burners reportedly started howling when the switch was made from gasoline to kerosine, and the Stanley Bros made many changes to deal with it. Not to mention varying temperatures and pressures at various points in the system. Changes in any of these factors can cause, modify, or eliminate howling, and the interaction between these factors seems quite complex. Amazing that a device as simple as a vaporizing burner can have so many things going on at once.
Definitely a fertile field for experimentation -- Mike's pressure gauge, Jim's frequency meter, and probably other instrumentation, would come in handy.
This thread (probably not over yet) has been extremely enlightening & thought-provoking, and I think a lot of ideas & info have turned up which will be very useful to steam car owners and experimenters in the future, for increasing reliability, controlling noise, and enhancing performance. Many of these considerations seem applicable to other types of burners (esp flameholder types) as well. Thanks to everyone for your excellent input, and to John Woodson for hosting these great discussions!
Peter</HTML>
Sounds like all these factors -- vaporizer, jets, mixtubes, grate, combustion chamber size, and flue -- have an impact on vaporizing burner noise. Fuel & combustion chemistry probably also play roles; Stanley burners reportedly started howling when the switch was made from gasoline to kerosine, and the Stanley Bros made many changes to deal with it. Not to mention varying temperatures and pressures at various points in the system. Changes in any of these factors can cause, modify, or eliminate howling, and the interaction between these factors seems quite complex. Amazing that a device as simple as a vaporizing burner can have so many things going on at once.
Definitely a fertile field for experimentation -- Mike's pressure gauge, Jim's frequency meter, and probably other instrumentation, would come in handy.
This thread (probably not over yet) has been extremely enlightening & thought-provoking, and I think a lot of ideas & info have turned up which will be very useful to steam car owners and experimenters in the future, for increasing reliability, controlling noise, and enhancing performance. Many of these considerations seem applicable to other types of burners (esp flameholder types) as well. Thanks to everyone for your excellent input, and to John Woodson for hosting these great discussions!
Peter</HTML>
Noisy vaporising burners
Posted by: Mike Clark (IP Logged)
Date: August 01, 2002 02:52PM
<HTML>Ray - although I started off thinking that howling is like blowing across a bottle, just an accoustic effect, I'm still not convinced. I tried air at 100psi through a venturi size tube - I could make it roar depending on how close the jet was to the entry but nothing like the burner howl.
Reducing the fuel pressure is pretty much the same as what happens when the steam auto is only partly open - in either case the flow of fuel is such that it all gets vaporised but as I have found with my vaporiser pressure gauge the pressure can drop way down to 40psi and the exhaust flue gases stay clean - only below 30psi does it start to smoke. Obviously the burner is very pressure tolerant.
I find the steam automatic often runs the burner in a modulating fashion - with the burner lit and the pressure floating from 40 to 100psi but not howling. The slightest wiff of throttle and it opens up going up to 120psi and if held there beginning to howl. The only bad aspect is when cruising slowly or going down a slight grade with little steam demand - then the auto opens up a bit, makes a puff of smoke and then shuts down again. I usually go down hill with the fuel valve shut to eliminate this.
Mike</HTML>
Reducing the fuel pressure is pretty much the same as what happens when the steam auto is only partly open - in either case the flow of fuel is such that it all gets vaporised but as I have found with my vaporiser pressure gauge the pressure can drop way down to 40psi and the exhaust flue gases stay clean - only below 30psi does it start to smoke. Obviously the burner is very pressure tolerant.
I find the steam automatic often runs the burner in a modulating fashion - with the burner lit and the pressure floating from 40 to 100psi but not howling. The slightest wiff of throttle and it opens up going up to 120psi and if held there beginning to howl. The only bad aspect is when cruising slowly or going down a slight grade with little steam demand - then the auto opens up a bit, makes a puff of smoke and then shuts down again. I usually go down hill with the fuel valve shut to eliminate this.
Mike</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Peter Brow (IP Logged)
Date: August 06, 2002 06:30AM
<HTML>Stanley Dealer Bulletin #54 (5-31-1918) says:
"WHISTLING BURNER.
"We have found that in some few cases the burners on the Model 735 will whistle slightly, when steaming up, or upon starting after a protracted stop. We find that there is a relation between this whistling and the strenght [sic] of the pilot. In the 735 there is a large vaporizer tube over the pilot. Unless the pilot is in good condition; that is, unless it is properly adjusted and sufficiently strong enough to keep the main vaporizer hot, this will have some effect on the burner whistling.
"Occasionally the burner will whistle, even with a satisfactory pilot, but in most cases the vaporizer nozzles are not in the center of the mixing tubes. First, see that the pilot is properly adjusted, and then see that the vaporizer nozzles are set concentric to the mixing tubes.
"Very truly yours,
"STANLEY MOTOR CARRIAGE COMPANY."
===========================
As if there aren't enough possibilities! Now off-axis jets and weak pilots.
It does sound as if incomplete vaporizing of the fuel can be a factor. Both this and off-axis jets could reduce the inlet pressure of fuel/air mix, and there may be other things going on.
Peter</HTML>
"WHISTLING BURNER.
"We have found that in some few cases the burners on the Model 735 will whistle slightly, when steaming up, or upon starting after a protracted stop. We find that there is a relation between this whistling and the strenght [sic] of the pilot. In the 735 there is a large vaporizer tube over the pilot. Unless the pilot is in good condition; that is, unless it is properly adjusted and sufficiently strong enough to keep the main vaporizer hot, this will have some effect on the burner whistling.
"Occasionally the burner will whistle, even with a satisfactory pilot, but in most cases the vaporizer nozzles are not in the center of the mixing tubes. First, see that the pilot is properly adjusted, and then see that the vaporizer nozzles are set concentric to the mixing tubes.
"Very truly yours,
"STANLEY MOTOR CARRIAGE COMPANY."
===========================
As if there aren't enough possibilities! Now off-axis jets and weak pilots.
It does sound as if incomplete vaporizing of the fuel can be a factor. Both this and off-axis jets could reduce the inlet pressure of fuel/air mix, and there may be other things going on.
Peter</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Jim Crank (IP Logged)
Date: August 06, 2002 01:57PM
<HTML>Peter,
Read this Stanley data again most carefully.
When the pilot is low, the hot dog on the main burner vaporizer is somewhat cooled down. So what is the result? Cooler fuel vapor and thus more dense.
I still am of the opinion, subject to instant change, that dense fuel vapor going into the venturi causes the howling. My Stanley did this under these conditions and so did my White.
The Stanley vaporizer was cut down, 3" at a time, until it whooped once if the car had to go through two changes of stop lights. In two years I never cleaned the carbon out, didn't have to do it.
Roland Giroux used to have a propane pilot in his 40HP White. Not enough heat compared to the White pilot and his car screamed like a banshee.
As the guy from Mobile told me: "Try not to let the vaporized kerosene go over 400-450°F and you will have much less carbon, because you are not breaking down the fuel".
Now someone will want an electrically heated vaporizer with computer control.
Jim</HTML>
Read this Stanley data again most carefully.
When the pilot is low, the hot dog on the main burner vaporizer is somewhat cooled down. So what is the result? Cooler fuel vapor and thus more dense.
I still am of the opinion, subject to instant change, that dense fuel vapor going into the venturi causes the howling. My Stanley did this under these conditions and so did my White.
The Stanley vaporizer was cut down, 3" at a time, until it whooped once if the car had to go through two changes of stop lights. In two years I never cleaned the carbon out, didn't have to do it.
Roland Giroux used to have a propane pilot in his 40HP White. Not enough heat compared to the White pilot and his car screamed like a banshee.
As the guy from Mobile told me: "Try not to let the vaporized kerosene go over 400-450°F and you will have much less carbon, because you are not breaking down the fuel".
Now someone will want an electrically heated vaporizer with computer control.
Jim</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Terry Williams (IP Logged)
Date: August 06, 2002 02:57PM
<HTML>>As the guy from Mobile told me: "Try not to let the vaporized kerosene go over 400-450°F and you will have much less carbon, because you are not breaking down the fuel".<
Not too far from saturation temperature on a Stalney is it? Anyone know of any steamheated vaporizers?</HTML>
Not too far from saturation temperature on a Stalney is it? Anyone know of any steamheated vaporizers?</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Pat Farrell (IP Logged)
Date: August 07, 2002 02:00AM
<HTML>With our Stanleys, I find that we get more howling in the cool damp air than we do in warm dry air. Running in the deserts, we usually never hear a howl at all. Firing up in the cool damp morning air, brings everyone to their windows shouting. "quite that thing down! Kind of fits what the dealer bulletin said about a hot pilot making a quieter burner.</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Peter Brow (IP Logged)
Date: August 07, 2002 05:22AM
<HTML>Hi Jim and Pat,
Whatever the physics, a strong pilot and proper main vaporizer length seem to be the solutions to burner noise. Long enough to vaporize all the fuel under all conditions, but short enough to minimize carbon buildup. Trial & error is the way to find the right length. Longer if you see vapor cones or have noise; shorter if carbon starts driving you up the wall. 2 years of driving with no carbon trouble sounds like "problem solved" to me; well done.
For cold weather howls, maybe an air preheater with a thermostat butterfly valve; could be very small & simple and heated either by main burner (faster) or by boiler exhaust gas. An air tube in firebox or exhaust flue to heat part of the inlet air would do it. But that may be gilding the lily a bit too thick; if everything else is right, howling should be only brief if at all.
Computerized electric vaporizer, LOL! There actually was a string on temperature-controlled vaporizers at Karl Peterson's Lightsteam List way back when. Electric might be a good way to heat the main vaporizer quickly at cold start, though. Works for later Stanley pilots.
Thanks for the 400-450°F kerosene figure, Jim. Wonder if the range for gasoline is different.
Peter</HTML>
Whatever the physics, a strong pilot and proper main vaporizer length seem to be the solutions to burner noise. Long enough to vaporize all the fuel under all conditions, but short enough to minimize carbon buildup. Trial & error is the way to find the right length. Longer if you see vapor cones or have noise; shorter if carbon starts driving you up the wall. 2 years of driving with no carbon trouble sounds like "problem solved" to me; well done.
For cold weather howls, maybe an air preheater with a thermostat butterfly valve; could be very small & simple and heated either by main burner (faster) or by boiler exhaust gas. An air tube in firebox or exhaust flue to heat part of the inlet air would do it. But that may be gilding the lily a bit too thick; if everything else is right, howling should be only brief if at all.
Computerized electric vaporizer, LOL! There actually was a string on temperature-controlled vaporizers at Karl Peterson's Lightsteam List way back when. Electric might be a good way to heat the main vaporizer quickly at cold start, though. Works for later Stanley pilots.
Thanks for the 400-450°F kerosene figure, Jim. Wonder if the range for gasoline is different.
Peter</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Peter Brow (IP Logged)
Date: August 07, 2002 05:32AM
<HTML>Hi Terry,
I haven't heard of any steam-heated vaporizers, but the idea was suggested on the Lightsteam List once. Maybe somebody has tried it. Sat. steam temp @ 500 psia is 467°F; 486°F @ 600 psia. Problem is, how to heat up a steam-heated vaporizer with a cold boiler (or no boiler in tests). Some early steam cars put the fuel vaporizer in the smoke cap or exhaust flue, giving about 400°F, longer vaporizer (no radiant heat) and slower warmups.
Peter</HTML>
I haven't heard of any steam-heated vaporizers, but the idea was suggested on the Lightsteam List once. Maybe somebody has tried it. Sat. steam temp @ 500 psia is 467°F; 486°F @ 600 psia. Problem is, how to heat up a steam-heated vaporizer with a cold boiler (or no boiler in tests). Some early steam cars put the fuel vaporizer in the smoke cap or exhaust flue, giving about 400°F, longer vaporizer (no radiant heat) and slower warmups.
Peter</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: George Nutz (IP Logged)
Date: August 07, 2002 10:26AM
<HTML>Pat and Peter,
The cooler, damper air has more mass and takes more energy to accelerate in the mixing tubes, in the desert the air would be very "light" and easier to add momentum to.
The distillation and cracking temperatures of gasoline are different, gasoline at a lower temperature. The end distillation temperature for kerosine is 500F, for motor gasoline 400F---this is from old data(everything I have is getting old!) and modern Kero and gasoline might be slightly different.
Best, George</HTML>
The cooler, damper air has more mass and takes more energy to accelerate in the mixing tubes, in the desert the air would be very "light" and easier to add momentum to.
The distillation and cracking temperatures of gasoline are different, gasoline at a lower temperature. The end distillation temperature for kerosine is 500F, for motor gasoline 400F---this is from old data(everything I have is getting old!) and modern Kero and gasoline might be slightly different.
Best, George</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Jim Crank (IP Logged)
Date: August 07, 2002 01:38PM
<HTML>Terry, Peter, George, et al,
Terry, never heard of a steam heated vaporizer. How would you start it up?
Peter, no electric heater on the main vaporizer, unless you could give it 300 amps to get it going!
George, right, kerosene has a higher cracking temperature than gasoline.
Seems as if this howling is just a characteristic of the pre mix vaporizer burner as in a Stanley or White. I guess one just lives with it. Part of the fun.
Roland Giroux once mentioned: " When a Stanley howls it is happy, when a White howls, look out, it is going to do something nasty".
All this is saying the same thing, really, it seems to be that when a given burner has a dense mixture, it tries to howl. A really hot pilot seems to be one aid in eliminating this effect.
I still wonder if the pitch of the howling is dependent on the venturi length?
Jim</HTML>
Terry, never heard of a steam heated vaporizer. How would you start it up?
Peter, no electric heater on the main vaporizer, unless you could give it 300 amps to get it going!
George, right, kerosene has a higher cracking temperature than gasoline.
Seems as if this howling is just a characteristic of the pre mix vaporizer burner as in a Stanley or White. I guess one just lives with it. Part of the fun.
Roland Giroux once mentioned: " When a Stanley howls it is happy, when a White howls, look out, it is going to do something nasty".
All this is saying the same thing, really, it seems to be that when a given burner has a dense mixture, it tries to howl. A really hot pilot seems to be one aid in eliminating this effect.
I still wonder if the pitch of the howling is dependent on the venturi length?
Jim</HTML>
Re: Noisy Vaporizing Burners? -- Official Stanley Opinion
Posted by: Peter Brow (IP Logged)
Date: August 07, 2002 09:10PM
<HTML>Hi Jim,
300 AMPS! I feel like the crazy inventor in "Back To The Future" -- "One point twenty-one gigawatts!!". Looks like I better check my specific heat tables and do the wattage calcs. I was "assured" that the amperage would be doable with a stainless vaporizer, by the guy who suggested the idea. Oh well, the pilot can warm up the main vaporizer, but there goes the quick startup from cold. Then again, car batteries will provide a few hundred(?) "cold cranking amps" for a few seconds. But whew. I'll check the numbers, thanks for the reminder.
If howling is from a resonance effect in the mixtubes, these can be tuned to not howl at any firing rate at normal air (& fuel vapor) temperatures, and a cheapo air heater can compensate for any increased-density problems, except perhaps for a few seconds at startup in cold weather. Add thermostatic EGR from firebox via flame barrier & diluter? Hmmm.
In some stock Stanleys or Whites, yep, one is probably stuck with at least a little howl now & then. Part of the car's personality.
Peter</HTML>
300 AMPS! I feel like the crazy inventor in "Back To The Future" -- "One point twenty-one gigawatts!!". Looks like I better check my specific heat tables and do the wattage calcs. I was "assured" that the amperage would be doable with a stainless vaporizer, by the guy who suggested the idea. Oh well, the pilot can warm up the main vaporizer, but there goes the quick startup from cold. Then again, car batteries will provide a few hundred(?) "cold cranking amps" for a few seconds. But whew. I'll check the numbers, thanks for the reminder.
If howling is from a resonance effect in the mixtubes, these can be tuned to not howl at any firing rate at normal air (& fuel vapor) temperatures, and a cheapo air heater can compensate for any increased-density problems, except perhaps for a few seconds at startup in cold weather. Add thermostatic EGR from firebox via flame barrier & diluter? Hmmm.
In some stock Stanleys or Whites, yep, one is probably stuck with at least a little howl now & then. Part of the car's personality.
Peter</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Mark Stacey (IP Logged)
Date: August 13, 2002 12:57AM
<HTML>The jets on the Stanley Y branch I've examined appear to be just a drilled hole.
Has anyone tried or know if there would be an improvement in efficency if the jet was reshaped to have a small throat section (of the standard drill size) but with a 60 degree entry 30 degree exit ie making it a DeLaval nozzle?
The theory being the improvement in velocity will improve pumping and thus reduce howling.
The second question is does insulating the branch make any difference to howling?
Cheers
Mark Stacey</HTML>
Has anyone tried or know if there would be an improvement in efficency if the jet was reshaped to have a small throat section (of the standard drill size) but with a 60 degree entry 30 degree exit ie making it a DeLaval nozzle?
The theory being the improvement in velocity will improve pumping and thus reduce howling.
The second question is does insulating the branch make any difference to howling?
Cheers
Mark Stacey</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Pat Farrell (IP Logged)
Date: August 13, 2002 03:01AM
<HTML>Insulating the branch fork has not made any difference in the performance or the howling on our model 606. The insulation does get in the way while preheating the branch forks upon firing up. I have made jets as you have described and I didn't remember to check if the howling was any different.
Unfortunately, they plugged with carbon easily. I presently use the Blazick type self cleaning jets with good results. I found that if howling is a problem, reduce your main fuel pressure or by going to smaller main jets would quiet our Stanley. Our 606 only howls while steaming from cold or in cooler weather. Today it is 80 degrees out and it ran without howling at all this evening.</HTML>
Unfortunately, they plugged with carbon easily. I presently use the Blazick type self cleaning jets with good results. I found that if howling is a problem, reduce your main fuel pressure or by going to smaller main jets would quiet our Stanley. Our 606 only howls while steaming from cold or in cooler weather. Today it is 80 degrees out and it ran without howling at all this evening.</HTML>
Re: Noisy Vaporizing Burners?
Posted by: ronald parola (IP Logged)
Date: August 15, 2002 11:29PM
<HTML>Regarding howl, itsa good noise, but does get tiring. On my 740 I do have a duct going forward under the burner, and enclosing the branch forks and venturis. This does preheat the air to some extent and does pressurise the burner at speed. This was done because on the 740 the burner faces rearward and when driving the air going by would cause it to backfire more; actually sucking air from the venturis. With this I can run a larger fuel jet than before without being too rich. This car did howl even when warmed up, but I just tried some even LARGER jets, and at the point of being too rich. With these the howl has gone away with the burner turned full on, at lesser fuel valve openings it comes back. I wonder if the howl at full fuel goes supersonic; it's there, I just can't hear it. I've gotta remember to check the dogs as I go by.Cheers Ron P</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Pat Farrell (IP Logged)
Date: August 16, 2002 03:22AM
<HTML>I have tried too large of jets in my main burner nozzels too. No howl, but a hell of a danger of fire. Going too large of main jet nozzels on a noncondensing Stanley will load the exhaust duct up with unburnt fuel until it reaches a point of ignition. I watched Mike Simpson's 1909 Stanley model R with a fire in it's stack. He drove along unknowing that fire was pouring out of his tail. The soldered joints of his stack became unsoldered and people were picking up stack parts off the road behind him. When the exhaust stack is on fire, it is hard to put out unless you have a steam enema to flush it out with. On the condensing cars, as you well know, the exhaust dumps directly behind the burner so you you do have the acumillation of raw fuel like the noncondensors do.</HTML>
Re: Noisy Vaporizing Burners?
Posted by: ronald parola (IP Logged)
Date: August 21, 2002 11:50PM
<HTML>Well not THAT rich, I gotta put it on our smog machine some day.Ron P</HTML>
Re: Noisy Vaporizing Burners?
Posted by: Jeff Theobald (IP Logged)
Date: October 27, 2002 08:24AM
<HTML>Hi All,
I got around to fitting the superheater to the Serpollet replica, this entailed fitting a one inch deep spacer ring under the boiler to make room for the extra pipework, this also increased the size of the burning area and going by what I had thought caused noise from the burner, I expected a change in the howling, to my surprise it howls and screams the same, so I was wrong in that theory, now I am as baffled as others as to cause.
regards, Jeff.</HTML>
I got around to fitting the superheater to the Serpollet replica, this entailed fitting a one inch deep spacer ring under the boiler to make room for the extra pipework, this also increased the size of the burning area and going by what I had thought caused noise from the burner, I expected a change in the howling, to my surprise it howls and screams the same, so I was wrong in that theory, now I am as baffled as others as to cause.
regards, Jeff.</HTML>
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