Amtrak’s adoption of Head End Power (HEP) for electrical heating and cooling has eliminated steam for heating and cooling on cars allowed to operate on Amtrak trains (both Amtrak cars and Amtrak authorized Private Cars).
You know, I never did see an answer to this. My assumption was that the Tubular Train did use existing ‘package’ genset equipment for the hotel power … but it might not have been OTS, and it might not have been 60Hz. Someone here will know.
It had to involve a evaporator of some kind, evaporate water and you get cool air the faster you evaporate the cooler the air is that is produced. I remember an experiment where with just some alchol we produced Ice in meterology course via rapid fanning with a theme book…rapid evaporation of a liquid.
Also, for the OP’s benefit, the steam was under pressure and they had thick pipes under the cars to carry it I think they were at least 2 inches across if not more. The joint between cars i think was screwed on (don’t remember) and I think they could shut off the steam under pressure while they made the connection between cars similar to the air brakes.
Servel is a well-known brand of absorption refrigerator – it used a similar cycle to the Electrolux Dometic: ammonia, water, and hydrogen, with no moving parts.
http://vintageservelrefrigerators.com/HowItWorks.html
Einstein and Szilárd, of later atomic device fame, patented a version employing butane instead of hydrogen.
You can make an air conditioner on this principle with little more than humid air, water and brine – using heat to concentrate the brine.
For true weirdness look up the IcyBall refrigerator, another ammonia absorption type, which Crosley made famous.
I was at a seminar on absorption chillers. My mind was boggled, I just could not grasp the concept and I still can’t. My boss asked me what I learned. I said, “They work by magic!” He laughed but I still had no comprehension of them so it might as well be magic. It was too much and it made my brain sting.
We had at least one thread on steam ejector air conditioning in which Erik provided a couple of really good detail drawings showing how things worked on a modern car. High pressure steam is allowed to flow fast enough to augment the pulling of a vacuum with shockwaves; water boils at the low ejector pressure and carries away the usual enormous latent heat of vaporization characteristic of water…
http://cs.trains.com/trn/f/111/p/260457/2928188.aspx
All you need to know about ammonia absorption refrigeration is that ammonia boils at a low temperature – it was and is an excellent refrigerant for that reason – and is also hellishly absorbed in cool water, but readily separated by heating that water. Read the operating principle of the IcyBall and the specific method to manually ‘regenerate’ and then re-start it for a straightforward account of a simple ammonia setup.
A number of years ago I had a Mini-motorhome. It used LPG for heating with a ordinary furnace as well as cooling the refrigerator by being the heat source for the amonia -compression - expansion - compression cooling cycle. The principles of cooling remain the same, no matter of amonia, freon or some other similar material is used. The air conditioner for the motorhome was run by 120v AC, which also supplied the heating element for the refrigerator when electricity was available.
When I was very young, we lived in Milwaukee and had a Servel Refrigerator. If I recall it was not very good at making ice cubes but then, we were not drinking cold drinks very much back then. In '43, we moved to Greenhills, OH where we did not have natual gas and I don’t know what dad did with it. The row house we lived in had a coal fired steam heat. No electricity used. No thermostat. Open dampers or shut them to control heat. In the fifties, after dad bought the unit, he converted to oil.
When I got a camping trailer in the '80’s I got a Dometic refrigerator that operated on 12 V dc, 120V ac, or propane. It operates on an adsorption cycle.
Now for RR’s the PRR’s E units had two steam generators, and two prime movers. PRR I presume wanted redundacy for reliabilty. A primay mfg of the steam heating was VAPOR. And the sleepers had individual thermostats and steam valves for each room, plus the other areas.
Back when the CB&Q first went to to bilevel commuter cars, they had steam heat but used a generator installed in a single level coach baggage car for lights and AC. They didn’t operate push-pull but had to turn the engine at each end of the run. After seeing how well PP worked on the C&NW, they went to HEP. Took the steam generators out and installed small HEP diesel generators.
And one more thing, the Burlington’s early Zephers had HEP generators for their AC, lights & heat. The Illinois Railroad Museum’s Nebraska Zepher still runs and a number of years ago ('81) took it out on the BNSF from Chicago to Quincy IL and back. It passed ALL inspections FRA, UP, BNSF, AMTRAK and itoperated at BNSF track speed, 79mph. The IRM crew even served meals cooked on the train. To me, that is an amazing feat.
Forgive the fans exuberance.
An attempt to explain the adsorption cycle is to think of a coffee percolator. The heat boils water and the steam pushes the water up the pipe to let it fall down through the grounds. In the refrigerator, the water mixes with the ammonia and then is heated. the heated water/ammonia moves like a percolator to a tank where the ammonia is de-adsorbed (becomes a gas) and then flows through the condensor where it cools and liquifies. Meanwhile the water returns back to the adsorbtion tank. The ammonia (now a) liquid flows through the evaporator where it returns to a gas absorbing heat from the area to be cooled and then flows back to the adsorbor where the water and ammonia mix again. Similar to the freon cycle, boiling and condensing.
We had a RV with a propane-fired fridge when I was growing up. It had to be pretty much absolutely level to work, Dad would shut it off before driving and level the RV with jacks before turning it back on.
Steam heat and electric lighting in railcars were massive improvements over the previous systems. Doesn’t coal stoves and gas lighting inside a wood car sound like a great combination in crashes!?
VIA Rail did not finish phasing out steam heated equipment until 1997, and for much of the transition period the new LRC and F40 locomotives could be seen paired with a steam generator car or trailing F-units of both EMD and MLW varieties.
All the comments about what’s needed to make an ammonia absorption cycle refrigerator work, emphasizes why Carrier went with the steam ejector for steam powered A/C.
The steam ejector was one of the first applications of supersonic nozzles and diffusers. The supersonic flow was needed to make sure the steam from the nozzles didn’t flow back into the chamber being evacuated. This was followed by a diffuser to slow down the steam and thus increasing pressure - a KEY POINT as it allowed condensation at a higher temperature than the water being evaporated for cooling.
From what I understand, steam ejectors are still being used to make condensed milk.