The Skinner Uniflow Steam Engine represented the height of efficiency of steam engine design when it was produced in 1926.
The uniflow design solved a fundamental heating-cooling inefficiency of other steam engine designs by allowing steam to pass
through the cylinder in one direction, utilizing intake valves in the head, and exhaust ports in the cylinder walls.
This engine originally furnished the electricity for the Stanford University-Presbyterian Hospital in San Francisco,
where it operated for nearly a half century. It is direct connected to a 150 KW, 250 volt direct current generator and weighs 43,000 pounds.
When the Stanford University Medical School bought the engine in 1926, it paid the Skinner Engine Company $12,307.
The engine has a cylinder diameter of 19 inches, a stroke of 20 inches, operated at 200-225 RPM, and utilized a steam boiler pressure of 125 PSI.
In 1974, Stanford Hospital switched to a more modern power supply, and the engine was donated to the Exploratorium at the
Palace of Fine Arts in San Francisco. It served as a demonstration object for the wonders of steam power until changes in museum focus
made the engine surplus in 1994.
In 1995, the Board of Directors of the Exploratorium donated the Skinner Uniflow Engine to Roots of Motive Power Inc.

Website;
http://www.rootsofmotivepower.com/default.html

And this one designed by Mr. Skinner might interest Speeder;






Imagine this...4 cylinder, 2 stroke, supercharged and rotary valve. Yes, rotary valve...four of them! This engine was designed and built by Mr. Skinner in the New England area during 1928-1929. The engine mounts and bell housing mounts are common to a Ford Model A. I have learned that this engine didn't have success in auto racing due to cooling challenges and was later used with better success (and cooling) in a race boat.. The engine was acquired together with the complete set of beautifully constructed wood patterns for sand casting. Interesting Technical Features: 1)water cooled cylinder block and head is cast as one unit from grey iron; 2)upper crankcase, oil pan, front chaincase and manifolds are aluminum sand castings; 3)supercharger is by Switzer-Cummins of Indianapolis, Indiana; 4)carburetor is a downdraft Stromberg; 5)cylinder head is machined to run two spark plugs per cylinder; 6)exhaust vents to atmosphere at BDC out the right and left side of engine (eight exhaust pipes); 7) although the engine is two cycle, there are no transfer ports; 8)whereas most four cylinder engines have a firing order of 1, 3, 4, 2 this engine has a firing order of 1, 4, 2, 3; 9)crankshaft big end journals are at 90 degrees to each other, counterweights are knife-edged and there are five pressure-fed main bearings; 10)pistons are flat top with three compression rings each (no oil ring); 11)each of the four rotary valves are shaped like a shot glass, only about twice as tall.

Each rotary valve has a slot in it that opens to the combustion chamber. The following is the mapping: (1) intake begins to open when the exhaust port is 50% open; (2) intake is 100% open when the exhaust port is 100% open (must have shot flames!); (3) intake begins to close when exhaust port is 50% closed; (4) intake is 100% closed when the exhaust port is 100% closed. Understanding this mapping, and the lack of transfer ports, explains the need for the supercharger. There is no event that will draw in the intake charge naturally. Mr. Skinner controlled the effective compression ratio by timing of the rotary valves and by positioning of the exhaust ports. He first ensured that complete scavenge of the spent charge took place and then closed the ports and rotary valves on pure intake charge which is only then compressed by the remaining piston travel available above the top of the exhaust ports. It is said that "everything old is new again". In the case of the 1930 Skinner prototype, this same thought process is being introduced in Uniflow diesel engines for both trucks and aircraft today.

website;
http://www.quincylooperracing.us/index.html

And back on steam,

http://www.youtube.com/watch?v=SuKzdm55FZ8

I'd really like to find an affordable unit/project for the cottage up north. A wood burning steam engine and electric generator to power the whole house! Alternative power!!! I GOTZ wood.

http://www.ebay.com/itm/U-S-Patent-6503072-Unity-Uniflow-Rotary-UUR-Engine-/250772065835?pt=LH_DefaultDomain_0&hash=item3a632e0e2b

Would it be possible to modify a v8 gas engine to run on steam? I've heard of ppl making them run on compressed air.
Keep the engine temp above 212*F to prevent the steam from condensing. Could even be run in closed loop so you don't have to add water.

Make the cam 1:1 ratio.

The coolant could first be sent to the house to heat it and the exhaust could pass through a heat exchanger...

Makoi wrote:

http://www.ebay.com/itm/U-S-Patent-6503072-Unity-Uniflow-Rotary-UUR-Engine-/250772065835?pt=LH_DefaultDomain_0&hash=item3a632e0e2b

Ha! I have a similar concept but different mechanics. This one is more elegant.

http://www.youtube.com/watch?v=5F9nB69FQjc

Dang that stuff is cool I bet that 2 stroke motor makes some power

Briggs & Stratton lawn mower to steam engine conversion on compressed air

http://www.youtube.com/watch?v=xmapdIx3vWA

I like the concept, but not to cut grass!

http://www.youtube.com/watch?v=O737vRLHYAw&feature=related

Neat. On the steam powered V8, would coolant even be needed? A steam engine isn't going to get any hotter than the steam feeding it, which is not going to be much more than 300 degrees. Plus, the cam timing is going to be completely different with a steam engine than with a gasoline engine. With a steam engine you'd need a sealed intake that can be pressurized, and the intake valve would need to open at top dead center so the steam can push the piston down. It would close at bottom dead center, and the exhaust valve would open. It would also run as a 2-cycle engine, as there'd be no need to have a combustion event or compression event. It would be a real pain to try and keep steam up on the road, but as a fixed engine like cabin power, it would work great. Wouldn't even need a V8, a 4 or 6 would work since a steam engine would be a 2 cycle. Every second stroke would be a power stroke instead of every fourth stroke. And, the exhaust would still have quite a bit of heat to it, and could probably be used to heat a copper ball with a curly tube coming out of the top as you only need to heat it to 9url=http://www.whiskeywise.com/Build-a-moonshine-still.html]173 degrees where water becomes steam at 212 degrees.[/url]

I like the V configuration because there's always a piston in the power stroke so it wouldn't stall.

The higher the pressure, the higher the temperature needed to produce steam.


The "coolant" could be used to keep the hot water at temperature. And to heat the cabin.


I wonder what compC would say... Yeah, I'd like a cam with 2 lobes per valves and 90* out of phase between the in and ex...

I also wonder about water bypass contaminating the oil??

Nah, the V is irrelevant on pistons and power stroke. It's cylinder count that matters for power strokes. The V design is strictly a packaging issue and is actually weaker than an inline engine as you have force being applied to the crank from two different, unopposed directions and you have two connecting rods between each set of bearings. An inline engine is superior because it has all force being applied from one direction, and has only one connecting rod between each set of bearings. This makes for a stronger engine. The downside of an inline engine is the more cylinders you have, the longer it is. Remember the cars from the 1940s? Super long, skinny hoods. In any case, you always have a piston under thrust with four or more cylinders as each piston is pushing on each 90 degrees of travel for the crank. The only thing more pistons does is give you a smoother rotation than fewer pistons. This is why an 8 cylinder runs smoother than a 6 cylinder, and why a 12 cylinder is smoother than an 8 cylinder.

Here's just history information, but it's interesting stuff about various types of engines.

http://www.citroenet.org.uk/miscellaneous/wankel/wankel1.html


project;

www.slamvalvemotor.com/uniflow.html



Last edited by Makoi on Thu Jan 19, 2012 3:53 am; edited 1 time in total

Speeder wrote:

In any case, you always have a piston under thrust with four or more cylinders as each piston is pushing on each 90 degrees of travel for the crank. The only thing more pistons does is give you a smoother rotation than fewer pistons. This is why an 8 cylinder runs smoother than a 6 cylinder, and why a 12 cylinder is smoother than an 8 cylinder.

No, that's just it! Inline 4s have a flat crank! When the 2 outer pistons are up, the 2 inner are down: 180* not 90*. So you could end up in a situation where the motor would not start in if it's at 0* TDC. And because it would work as a 2 stroke, it would not be smooth. Always 2 pistons pushing in phase.

Since chevy v8 are plenty-full, I'd rather use a v8 with only the amount of pistons needed.

And this thing would not be powerful at all, so the V weakness is not an issue.

As long as it can power a 5000W generator, that would be pretty cool... If a 4L could do it, that's fine too.

You know, using a blower would probably end up being easier to use...

5000 watt a small engine will do that. Makoi what about just running a standard generator off wood gas?

Whipped383 wrote:

5000 watt a small engine will do that. Makoi what about just running a standard generator off wood gas?

Yes but how much power can a steam powered piston engine generate?

Wood gas in a small engine is awful dirty. I saw a video of a guy's Briggs converted, and he was using it to charge batteries. Terrible cloud of smoke. A boiler fired by an airtight stove would be more efficient, less offensive, and probably quieter way to generate electricity. You know they used these all the time on ships to power the lights on board. Unless they sunk the ship, there must be hundreds of these things stored away in old warehouses up and down the east coast. I'd bet a lot of them were junked for the scrap, but there must be some survivors around. The thing is, a restored working unit that can generate electricity can cost over $30,000.00. Collectors and speculators!!! They're ruining everything, making stuff too expensive that I want to buy for my own fun.

uniflow steam engine

http://en.wikipedia.org/wiki/Uniflow_steam_engine
In small sizes (less than about 1000 horsepower), reciprocating steam engines are much more efficient than steam turbines. The Whitecliffs solar steam power plant used a three-cylinder uniflow engine to generate about 25 kW electrical output.

The single-acting uniflow steam engine configuration closely resembles that of a two-stroke internal combustion engine, and it is possible to convert a two-stroke engine to a uniflow steam engine by feeding the cylinder with steam via a "bash valve" fitted in place of the spark plug.[4] As the rising piston nears the top of its stroke it knocks open the bash valve to admit a pulse of steam. The valve closes automatically as the piston descends, and the steam is exhausted through the existing cylinder porting. The inertia of the flywheel then carries the piston back to the top of its stroke against the compression, as it does in the original form of the engine. Also like the original, the conversion is not self-starting and must be turned over by an external power source to start. An example of such a conversion is this steam-powered moped, which is started by pedalling.
The Whitecliffs solar steam power plant also used a three-cylinder uniflow engine with "bash" type admission valves.

We should start a company and make wood buring boilers with Uniflow engines attached to electrical generators that would be capable of 20KW. That would be enough to power the average house. Not everything on all at once, but plenty for the fridge, stove, etc... as you'd move from one room/activity to another turning things off behind you.

If you could get them priced around $7500.00, they'd probably sell pretty well.