<HTML>Hi Caleb,
About 20 years ago (start "Gabby Hays voice") when I was first getting into steam cars, I met local Stanley owner Jim Doughty at a classic car show at the local Auto Museum. He had a nice '20s Stanley Touring off in some remote corner of the display area, pretty much ignored by the crowd. It was the first time I had ever seen a steam car first-hand. I introduced myself, pestered him with technical questions, looked at everything I could see, and after a while he jacked up one wheel, pulled off the radiator cap, and cracked open the throttle. The raised wheel turned incredibly slowly and smoothly, and the radiator cap gave a very soft chuff chuff and blew puffs of steam about 10 feet in the air. I think that every person at the show, including the other car owners, abandoned the other cars and crowded around the previously-ignored Stanley to watch this and ask what the heck was going on. After that, I couldn't get a word in edgewise and soon left. A few years later I read in the paper that this car was tragically destroyed by a rampaging horse at a local parade! Perhaps horses still harbor some resentment at being sidelined by these upstart machines ...
Anyway, so yes, it is nice to hear that engine and watch the steam sometimes. Even gas car folks are fascinated.
The hamster wheel, squirrel cage, or "Scirocco" fan is the most efficient type. Good choice. Much more efficient than a propellor fan. Best for anything needing a fan, if you can find the room.
In the Steam Automobile Bulletin, somewhat more recently, somebody(?) estimated that you could use 1/6 the radiator area if you condensed the steam with a water spray and kept the radiator full of water.
Check out "[John] Wetz's Handy-Dandy Percolator-Circulator Condenser" in Vol. 26 #1 of The Steam Automobile (back issues available from SACA Storeroom @ [
www.steamautomobile.com] ). This has a small-diameter column of water into the bottom of which the exhaust steam is percolated (ideally with a screen or perforated flow divider to break it up into small bubbles). As the steam bubbles rise in the column, they rapidly condense into the water and also set up an upward flow in the column. The hot water spills over into the top of a water-filled radiator, circulates down thru the radiator as it cools, and exits the bottom of the radiator as it is drawn back into the bottom of the percolator-condenser column. Excess water (condensate) overflows from the top of the radiator, and returns to the water tank. Column is as tall as radiator, and connected to it at top & bottom. There are a couple other interesting wrinkles in his system too, details in the article.
This gives the advantages (if any) of a water-filled radiator, without an extra steam-to-liquid heat exchanger. H.O. Baker tried the secondary heat exchanger idea you mentioned, BTW, and it took up a huge amount of space in his car.
The downside of a water-filled radiator is possible freezing in cold weather, but the antifreeze-capable 2-stage condensing system is an overkill solution to that, IMO.
I am looking into the Saab/Philips "v-front" radiator/condenser, which has 4x the surface area/condensing capacity of a conventional radiator, for a given volume. Not commercially available to my knowledge, and a challenge to build (looking into that too), but a lot of condensing power in a small space. See my & Peter Heid's latest posts under "Condenser/Boiler Area Ratio" in this forum for description & comments.
I do think it is theoretically possible to get nearly complete water recovery, but it takes some doing in the design department. Peter Barrett uses a very large condenser (conventional type) with electric fans in his modern steam car, and reported no measurable water loss in some runs. And that is a rear-mount unit, drawing air from the back of a hot boiler/engine compartment, with little or no natural airflow.
Peter</HTML>