Gasometer - constant pressure fuel

[RHudson]

gasometers (float type) used an inverted bucket to store/supply fuel under a constant pressure and to also control fuel flow into the gasometer. is there any reason that i cannot use a lp regulator, 11 inches water pressure (thats about 0.4 psi) to feed lp into an inverted bucket. in this setup the regulator would actually do the work of controlling the fuel flow into the setup. the inverted bucket would only store and then supply its contents to the throttle valve. seems this would be superior to using a tank accumulator which will have a decreasing flow rate and decreasing pressure as fuel is drawn off. seems by being able to see the bucket rise and fall and how much it rises and falls i would know alot about whats happening with the fuel supply. and, of course the public gets to see another doohickey move around while the engine is running....or am i way off base? Thank for any thoughts Fellows.

[W.P.Klein]

Don't overlook that the wet gasometer's "inverted bucket" had an arm from it controling a gas valve so it shut the flow off when the float rose. You would need a physical stop to keep the float from coming up far enough to release the gas. Bill Klein

[ListerDiesel]

Always used to fascinate me as a kid in the 40's and 50's, these huge round containers that every town had, and they were always a different size every time you went past them!

Only later did I find out what they were, and now they are virtually all gone as we have piped natural gas from Russia :-))

As far as your own project goes, there is no reason not to use a smaller version as a storage medium for low pressure gas, but you would have to make sure it was properly sealed around the edges to prevent gas leakage, and as has already been mentioned by Bill, some sort of cut-off to stop build-up of pressure.

Would be an interesting item to knock up out of the odd gas cylinder maybe, but you would need two cylinders that fitted one inside the other closely so you could effect the sealing easily.

The cut-off valve could be done mechanically with not much trouble.

Let us know if you go ahead please.

Peter

[kerogas]

http://baserv.uci.kun.nl/~hvreenen/2...n/DSCN0015.jpg



That , my friends , is a gasometer .

[Joel Sanderson]

If your gasometer is essentially a reproduction of an old one, which would turn the gas on and off, then that is what would determine the pressure going to your engine and not the regulator before it.
Regarding a fixed gas reservoir, the Bessemer manual recomends it be six times the engine's displacement. A chamber that large would not drop in pressure appreciably from the beginning of the breath to the end; by the next revolution it would be back to the regulated pressure. I really doubt that this would be an issue at all unless the engine is working hard and drawing a full charge.

[Jim Gorter]

I built a wet gasometer (float type) for my 15 hp Reid project. I built the cylinders from galvanized sheet metal to have a 1/8 inch gap between. I filled the bottom cylinder with used crankcase oil. I hooked up a crude manometer to it and it only puts out about 4.5 to 5 inches H2O. Plenty to run the reid as fast as I would want to be around it.. Picture of the gasometer with the Reid at http://www.flicker.com/photos/rusty_acres/
I believe the cylinders were about 17 inch in diameter. Jim.

[Jim Gorter]

Sorry for the address: http://www.flickr.com/photos/rusty_acres/

[Kirk Taylor]

It could be done, but...................the project would take some calculating and ingenuity. In order for the "floating" cylinder to actually float and move up and down with changes in gas pressure without floating right out the top of the outer cylinder, it would need to 1) be the correct weight, which is easy to do; 2) actually displace a considerable volume of water. A simple tin can like a wet gasometer won't cut it. If I calculated correctly, a 10" diameter cylinder made from 0.025" thick steel and weighted to be buoyant in water would rise 6" with a increase in pressure of only 0.09" water column. A BBQ regulator isn't nearly precise enough to maintain that constant of a pressure. A wet gasometer is precision enough to do it, but that would sorta defeat the purpose of the whole project. If you made your gasometer 10 feet tall, you'd be ok. Or, if you had a floating cylinder with either sealed walls say 2" thick or a sealed inner cylinder (a piece of pvc pipe sealed on the bottom end fastened inside the floating cylinder), you'd probably have a more reasonable movement with changes in pressure because of the greater displacement.
Confused yet? I'm almost there.

Kirk

[Jim Gorter]

The size of the gasometer would depend on the volume of gas needed to run your particular engine. My 15 hp Reid pulls the inner cylinder down, but it runs at a kind of equilibrium, not having the floating cylinder move up and down too much. The volume of low pressure gas available at 4.5 inches H2O is 17 inches diameter by about 24 inch tall. A smaller diameter cylinder would show more "action" on the intake of gas. after i shut off the propane at the pressure cylinder, the engine will continue to run on the stored gas for a minute or better until it has consumed the volume of low pressure gas in the inner cylinder. I just estimated the diameter of the cylinders from pictures in the reid engine catalog. Jim.

[Ray Ethridge]

Here is a picture of some gasometers I saw at Coolspring. I have no idea what they were for, perhaps some of the Coolspring people can fill us in there. Basically they were similar in volume to what Jim is describing, except the two smaller ones are about 2 feet in diameter and maybe 18 inches tall, as a wild guess based on my memory.

[Jim Gorter]

Hey Ray, Looks like 3 different sizes there. With a little more curled copper pipe I could imagine a nice little still just cookin away. Jim.