Williams ws. Rankin

Harry,
What I don't like about bump valves is the symmetrical timing. Not so hot when trying to use one to power a car. What you say is true about using one.
How does silicon nitrite stand the pounding from the piston pin, any cracking?
Try the seat being harder then the ball, then just replace them once in a while.
Might be useful in an auxiliary engine though, start it by motoring the blower motor through a one way clutch.
Although using one sort of locks one into using a single acting engine and that oil contamination problem.
JC

Thanks Harry and Jim,

The bump valve then sounds usable under these circumstances. The engine is to be a compound with the bump valved stage just one of three. The engines direction of rotation is determined by the other stages so no start/stop or reverse problems. The clearance is very large. Cutoff about 7% re-compression in the 3/1 range.

What I like about the bump valve is that any over compression just goes back into the steamchest so the problems of regulating re-compression pressure is simplified.

With the silicon nitride ball what is used as a pin on the piston? Are there standard ball sizes?

Thanks, ------- Bill G.

Ps: Hello Chuk

Hi Bill

heard of a magneticly latched bump valve. It's bumped open and held open by an electro-magnet. So you have variable cutoff when it is released. Don't remember the source though. Or if it was ever used. But sounds like it could work. Simuler to the magnetic-latched valve I am working on.

Andy




Edited 1 time(s). Last edit at 05/16/2007 01:53PM by Andy.

Hi
Silicon Nitrate is very hard, if you hit it with a ball peen hamer it will dent the hammer. Never seen one break and used a lot of them. Never wore one out. I would never use a bump valve for a car engine. We are using it on the small generator lawn mowers and weed eaters or other small constant speed engines. Also I think it would make a great dragster using an outboard motor hooked to a transmission.
Harry

Hi Andy:

You are referring to the engine in the Simplex "Electronomic" Steam Buggy. Inventor was Ralph O. Hood. US Patent Number 694,547 issued on 4 MAR 1902.


Currently up to 3,950 patents in the indexed, hyperlinked database. Hopefully will be ready for public consumption by this summer.

Regards,

Ken



Edited 2 time(s). Last edit at 05/16/2007 02:57PM by frustrated.

HI Bill
You can get the silicon nitrae balls in McMaster Carr The pin is ss and will mold to the ball.
Harry

Hood built two of these cars,,,and drove one from Boston area to New York City and back,,,quite a feat,,as going past western Ct is soft sandy sink in type of going,,,,One car had a round coil,flash geneator,,the other was wound back an forth in a square shape,,The cars were never sold,,and still survive,,,Cheers Ben

HI Jim 15 years a go I made a rotary valve as a test. It was just valve exzorsstimg to atmmestfear. I ran it wig a motor it was in the shape of a cup with the valve rotor ran on columns with ports wore dilled throgh the columns. I made a bash valve engine tow stroke with a sillander sleeve the ports wore milled down the sleeve so the exhaust went in to the crankcase and out a hole in the bottom. The oil in the steam oiled it will

Harry,

I just want to know how your getting along with the 'piston-pin to Ball' injector without a recoil spring? I noticed in one of your preivious drawings, that the injector movable-body(ball) could be 'nudged with precise movement' such as a 10th of a mm. How do you deal with kinetic-shock for the impact-zone of the movable body per-event. You have not mentioned a dampining-system. Its my understanding the harder the substance, the more intense recoil intensity, per mass at a given stroke and frequency. You must be getting one hell of a vacuum off of the port diameter that you are working with.

Just curious...

The heat exchanger coils being super-imposed over the cylinders intregues me. Since temp drop is negledgable within this configuration, barring exhaust zones.

Jeremy

Hi Howard,
Yes, that would work, and Dick Smith did the same thing years ago, rotary distribution valve. Bump valves too, it was all the rage then.
Many others followed suit with converted Mercury outboard engines, using both the unaflow exhaust the two stroke engines already have, plus using the transfer port for exhaust into the crankcase and then out the carburetor openings.

My number one dislike with reciprocating steam car engines, is that damage that the oil does in the coils of the steam generator and condenser. Carbon and much reduced heat transfer in the condenser. There are other reasons too; but oil in the feedwater is the main concern.

Harry is doing good things with his new engine; but until he makes some very long term endurance runs, we will not know if oil can really be eliminated. I watch his work with great interest.
If an oilless piston ring is proved to really work for a long time, then we will have one big leg up on this problem.
JC

Hi Jeremy,
The silicon ditrate ball is hard where as the seat and pin are a soft stainless. The cut off is very short and is not as dramatic as it would appear as following the crown of curve. About 1000f is about the limit on the spring. There are updates on how we are handeling this problem Of course the two cyl engine was always designed with this in mind as a recomendation from Jay Carter.
The port opening of course would be far to small if the preasure were not so high (2000psi) and cutoff so short. These pump pressures with zero leak back and durability have been a task.

Hi Jim
The bearings and rings would not be possible a few years ago and some experimentals materials were not avalable a few mounths ago. It Is not just the materials but the combinations of them and their shape and clearances that have to be tested. Not as much ring problem as you might expect. The seceret is it has to be CLEAN.
Harry

Harry,

What happens to some of these materials such as the peek when they have to work with a bit of oil?

While we are on the subject of oil, what would be the best type of oil pump for a steam engine? Gear, star rotor, mechanical driven off the crank or electric? My variable cutoff and advance mechanisms are rotary hydraulic servos and I am thinking of up to 100 # pressure for the oil to servos and bearings. This would be a dry sump system.

Thanks, ------ Bill G.

HI Bill
Peek and oil are compatable and work well, same friction as water in that inviroment .004 never use water with metal bearings. We have settled on gear pumps engine driven. The peek can start up dry, metal bearings would hurt. Some automotive transmissions are using a peek bearing on a pilot shaft where it is hard to lube.
Harry

HI Jim duds the doble lab still exist and if it duds could it test and engine

Hi Howard,

The Doble lab vanished around 1935.
The Besler lab, in the same room, was dismantled and closed down many years ago.
The old plant is now live-work lofts.

Jim

I keep hearing about a Williams Engine. Is this what you are referring to?

This was a project in Australia and one of the Designers is named Williams.





Edited 2 time(s). Last edit at 06/30/2007 11:30PM by grblake.

I keep hearing about a Williams Engine. Is this what you are referring to?

This was a project in Australia and one of the Designers is named Williams.

Hello George,

What the drawings show is a Bump valve engine. The Williams engine discussed here is a design and build from the Williams brothers. It is distinguished by being a high compression Unaflow.

The advantages of recompressing all the way back to inlet steam pressure before the inlet valve opens are great from an efficiency point of view. This recompression eliminates the thermodynamic effects of clearance which would otherwise create a free expansion of the inlet steam as it is filling the cylinder to inlet pressure. The work losses from this free expansion are far greater than most people realize and are one of the big reasons for the steam engines time honored thermodynamic inefficiency.

The Williams engines, by much eliminating this clearance loss factor, have much inproved efficiency over non high recompression engines. The use of the Unaflow design over that of the counterflow design, even using full recompression, also increases efficiency by giving the same work output as the counterflow with less (about 60%) displacement.

Best Regards, ------- Bill G.

HI Bill as far as I no all the Williams had pop it vals most had camshafts vay wore working on a experimental valve gear.

Bill,

Is there a drawing like the one I have of the Williams? I would be interested in using part of it for my Solar project.

The Laws of Thermodynamics says, "There is no such thing as a free lunch".

After reading the thread and listening to others talk about this, I have to ask if the Williams engine was supposed to re-compress most or all of the steam? If that is the case, then I cannot see how you gain efficiency if the other cylinders are working to use their steam to re-compress that of the cylinder under pressure? That would make more work directed away from the output and defeat the purpose of the engine.

How much of the total net volume from the initial steam inlet does the Williams re-compress?

I am also reading where they did not complete the engine, lost funding, and subsequently shut down? How does that make for a successful engine?

Hello George,

As far as I know the better displays of the Williams engines workings are in their patent drawings. Someone else may be able to list some of those numbers. Looking them up with the "patents to pdf" website seems to work the best as they don't hold back the images or try to make them hard to read like many others.

Tom Kimmel also has several of the Williams engines for display, so you can see and touch them at the steam meet comming up this September.

From my studies on solar collectors and engines for same, I think that the engine would need to be designed for a specific range of collector input. One would then need to know the pressures, superheat temperatures, and pounds /hour, and the other parameters the collector is normallay putting out and design the engine around that.

Also a collectors output, and the electric generators load demand should be more constant than any car engines. This can bring different considerations to the engines design. I wouldn't rule out a small, high speed turbine /generator for this application. I am thinking here of perhaps one of the radial inflow types like a turbo-charger uses. Some of these are already well developed for small gas turbines and may be comverted to dry steam.

My concern with parabolic collectors was more in keeping the mirror surface clean than anything. It collects dust and haze which degrades focus and efficiency. A cover needs cleaning. It is like a car windshield. The things will need more tending for that reason than mechanical ones. Glass mirrors eazyier to clean but heavy and expensive, aluminized mylar light and cheap but scratches easier and focuses worse. Things and materials probably better and different now.

The tighter the design focus the harder it is with the mirror surface. Flat plates are the easiest but the temps are too low for thermal efficiency, thus requiring much more collector area. Rectangular or line focusing parabolic or cycloid collectors are more sensitive to focus and the temps should run a steam boiler under desert sun, the parabolic being the better of the two. The circular type can be made from old satellite TV dishes, while sheet metal will make good line focusing ones as it naturally springs into a parabolic shape.

All this was pretty long ago, but is still enticing.

Best, ----- Bill G.

Bill,

Thanks for the info.

Since I am more literate at Parabolas and Positioners than steam, here is what I am doing:

I am starting with a 10-foot TVRO dish, then I am adding Acrylic Mirrors to the surface to keep the contour. These have the metal sandwiched and are adverse to temp and scratches or pitting. They are also near perfect reflectivity since they are considered true mirrors. Then, I am adding a water spray from the supply tanks to clean them occasionally with the water returning back through the center hole to the tank. Since I have filters for the steam water already I am not concerned about dirt. Since the water will be quite a bit hotter than normal it should aid in cleaning the haze off, if any collects.

Since the Aussies used the bash valve Lister / GM combo, I was going to start with that design. If the Williams is different and better, I am all ears. I need the most efficient, buildable engine I can find.

I am also going oilless and using roller bearing, carbon graphite, etc. to get away from oil and raising the temp / pressure higher. I know some dandy synthetic greases we use in the aerospace industry that have a wide temp range.

If someone has the patent numbers I can search and find them.

Thanks.

The Williams basicly a valved uiflow engine. It has a variable clearance mechanism so as not to ever over compress.

The laws of theodynamics are not being broken. They can not be broken.

Positive displacement Rankine engines all have some clearance. Compression basicly eliminates clearance loss.

The Rankine cycle is not exactly correct for steam engines. It is a aproxamation that excludes all time dependent processes. There are three basic types of Rankine engine cycles And three system cycles. The engine cycles just figure engine processes where system cycles include external processes. Rankine cycle do not include losses due to heat transfer within the engine or anything other theodynamic processes. The three basic types of Rankine cycles are:

Full expansion cycle. Steam is expanded to exhaust pressure in the cylander as the exhaust opens.

Partial expansion or incomplete expansion cycle. Steam is expanded to some pressure above exhaust exhaust pressure when the exhaust opens and free expands to exhaust pressure. However I have not been able to find what process to use for a free expansion.

Non-expanding cycle. Inlet valve is opne for full expansion. No expansion occures. A feed water Donkey Pump is an example of this cycle.

Today the partial expansion and non-expanding cycle are not talked about in theodynamics books.

Turbine operate on the full expansion cycle. And aperently is now the standard cycle all engines are compared against. It hasn't always been this way. My old books compare an engine against an equilivant cycle and compute engine efficiency aginst the equilivant cycle. The full expansion cycle is the most efficienct as it extracts all expansion energy.

There are seeral ways to calculate engine output. The simplest relays on the conservation of energy law. and states that work_out = Work_in - Work_rejected.

And that is the way most books use to calculate the full expansion cycle. Work_in = BTU_in_inlet_steam. Work_rejected = BTU_in_exhaust_steam.

Work_out = H.in - H.exhaust

How ever we can calculate work of the seperate processes and come up with the same formula as above. That is for zero clearance. How ever when clearance is put into the formula we are lossing some of the constant pressure work. The work done by admiting the clearance volume of steam. With clearance:

Work_out = H.in - H.exhaust - P.in*clearance/J

What the Williams engine does is compress residual steam(steam left in the cylander when the exhaust valve closes) to inlet pressure so you are not filling exhaust space with fresh inlet steam. It eliminates clearance loss. The output power reduced by compressing the residual steam. But that power given back upon expansion. The shaft work is reduced by compression work. You are only producing work from the inlet steam. In theory, eliminating clearance loss, you would be geting the ideal cycle efficiency. However in a partial expansion cycle the exhaust steam, having retained some amount of it's heat content it had when the exhaust opened, compresses to a higher temperature then the inlet steam. You wind up with a higher temperature at cutoff then the inlwt steam and upon expansion the process work is increased. You also have less steam(by weight) filling the clearance space then a full expansion cycle. I can not explain where some efficiency is picked up. But calculating the cycle by process it does come out more efficienct then the equilivant zero clearance cycle. One has to be careful here. This only happens for a significant pressure drop from end of expansion pressure to exhaust. As you aproach a full expansion cycle the compression efficiency gain decreases. A full expansion cycle has no efficiency gain from compression. Only clearance loss elimination. The efficiency gain of a partial expansion cycle never puts the cycle efficiency greater then a full expansion cycle. The Williams engine was not the first to see an efficiency gain from compression. My old theodynamic bookd talk about uniflo engines being able to get higher efficency then predicted by it's equilavant Rankine cycle.

Andy

Hi GR,

The single most relevant Williams patent is US Patent Number 2943608. Easiest way to see the patent is to go to:

[www.google.com]

and type the above patent number into the appropriate space and hit enter.

The Williams engine was basically just a high compression uniflow with a poppet valve and a relief valve in the head that dumped excess recompression pressure back into the steam chest. Basically it appeared that about 40% of the power developed in the expansion stroke was expended recompressing a portion of the remnant steam mass in the cylinder back to the admission pressure. Since the compression ratio was higher than the expansion ratio the recompression energy would always be less than that developed by expansion.

The basic argument is that while output would be lower, efficiency would be higher. Two reasons were postulated, first being that by recompressing to admission pressure there would be no loss of pressure when the valve opened and steam from the chest was admitted to the cylinder. The second argument was that the temperature of the recompressed steam would be higher than that of the admitted steam from the chest and this extra temperature would permit greater expansion and better thermodynamic efficiency. I'm personally a bit skeptical of the last claim as it seems to rest on the claim that the polytropic coefficient of expansion and compression are different in an advantageous fashion. I'm not denying this is true, but I haven't seen definitive, irrefutable proof-positive establishing this as fact either.

The Williamses built a number of engines of varying configuration and displacement. Some appear to have auxiliary exhaust arrangements. I'm not sure any single sets of drawings are floating around that actually define their various plants.

Regards,

Ken

Hi Ken

Full compression to inlet pressure on partial expansion cycle does calculate out to have higher efficiency then a zero clearance cycle.

For that to to work the residual steam must retain a good amount of heet during free expansion when the exhaust opens. Any pressure drop with heet retation winds up increassing entropy. So the residual steam is compressed starting at a higher entropy then the expansion steam. In turms of temperature. A full expansion to exhaust pressure will result with compression starting from that temperature and compress along the same isentropic line. In a partial expansion the temperature doesn't drop as much and after exhaust is still higher then if had expanded to it's curent pressure. So starting at a higher temperature and compressing to inlet pressure the temperature will be higher then at cutoff.

Calculating a compression has a catch 22. Sense compression to inlet pressure results in an increased temperature even when mixed with the inlet steam the properties at cutoff must be calculated as a mix of compressed residual steam and the fresh inlet steam. The cutoff state is dependent on the mix of inlet and residual steam. And we do not know the state of the residual steam until we can calculate to cutoff state. My cycle calculator program recalcuates the cycle repeatedly until the enthalpy at cutoff stabilizes to some number of significant digits. Curently 6 digits. It initially uses a residual state the same as the inlet steam. On each iteration it gets closer. The calculator on my site uses a constant enthalpy process for free expansion. My old text books said engine valves ae an example of an isothermal(isoenthalip for real gass) process.

We also have the uniflow test chart submited on another thread showing the increased compression temperature of twice the inlet steam temperature. Though I am sceptical that the temperature could drop completly to inlet temperature during inlet.

Andy

Hi Andy:

Sorry to sound cynical but the only thing that is going to convince me that we are getting recompression temperature above admission temperature when recompressing only to admission pressure is a simple set of well verified experiments measuring the temperature and pressure of the steam before expanding in a cylinder and the same measurements after expanding. Also need to measure the work in and the work out to ensure that we aren't expending extra energy in recompression to get any temperature increase.

Calculations based on someone elses reported measurements or calculations based on thermodynamic theory are not going to budge me. Call it mule headedness but I don't think this is an unreasonable position. Doesn't even have to be a test engine, just a simple cylinder set up to do the measurements.

Note that I have NOT said this is a bogus claim, I have merely said it is not proven beyond all doubt. You haven't convinced me and based on calculations you just aren't going to convince me, until proven based on actual tests I am going to maintain that it is a debatable point. When working as a machinist I have a rule never to stack dimensions as the tolerances eventually result in an unworkable component. When engineering I prefer not to stack assumptions for the same reason.

I'm not arguing the point, not going to get into an argument, and not even trying to convince anyone else. This is just my position.

Now let's all be friends and move on.

Regards,

Ken

Hi Ken

I tend to think compression increasses efficiency in the case where there is pressure drop to exhaust pressure. I agree that there is so far no acceptable prof

The chart I was talking about was posted by Peter Heid in the Uniflow Vs Counterflow topic:

[www.steamautomobile.com]

I think it came from the Stumpf Unaflow book. I have some problems with that chart myself. Can you explain how compression temperature reaches 962F and the steam temperature drops to 470F mixing with 470F steam. I would not expect mixing any significant quanty of 962F steam with 470F steam to wind at 470F. Where did that additional heat go? 470 is susposidly the steam and head temperature.

I can do my own tests. But any experment must be reproducable by others.

There are some unknows. The temperature could be reaching the 962F because of initial heat content or compressing to higher then inlet pressure.

Just curious. What are you thoughts on that chart.

Andy




Edited 1 time(s). Last edit at 07/02/2007 06:17PM by Andy.

I have a question: What if I could get the heads and cylinders almost as hot as the inlet steam and keep it that way? Tom Kimmel suggests that such an engine would greatly increase the efficiency over traditional engines. If this were applied to the uniflow, what would happen?

All files from this thread

File Name	File Size		Posted by	Date
ThrottlingTurnDown.pdf	58.1 KB	open | download	Andy	11/22/2005	Read message
ThrottlingTurnDown.pdf	62.3 KB	open | download	Andy	11/22/2005	Read message
hydro.jpg	123.5 KB	open | download	HLS	02/14/2006	Read message
P1010001aa.JPG	113.5 KB	open | download	Rolly	03/09/2006	Read message
P1010003aa.JPG	66.8 KB	open | download	Rolly	03/09/2006	Read message
P1010002aa.JPG	65.3 KB	open | download	Rolly	03/09/2006	Read message
SingleExpansion Vs Co.pdf	111.7 KB	open | download	Andy	03/10/2006	Read message
SingleExpansion Vs Co.pdf	111.6 KB	open | download	Andy	03/13/2006	Read message
HLS Vs Compound size.pdf	112.1 KB	open | download	Andy	03/13/2006	Read message
HLS Vs Compound =PD.pdf	111.7 KB	open | download	Andy	03/13/2006	Read message
HLS engine.pdf	64.8 KB	open | download	Andy	03/14/2006	Read message
HLS engine.pdf	73.6 KB	open | download	Andy	03/15/2006	Read message
Rankin.pdf	171.9 KB	open | download	Andy	03/15/2006	Read message
HLS engine.pdf	74.6 KB	open | download	Andy	03/15/2006	Read message
Endiing temp 850.pdf	28.2 KB	open | download	Andy	10/02/2006	Read message
Endiing temp X27.pdf	28.1 KB	open | download	Andy	10/02/2006	Read message
Fickett.JPG	66.9 KB	open | download	frustrated	10/05/2006	Read message
Over Expansion 1.pdf	24.2 KB	open | download	Andy	10/24/2006	Read message
FlowSpeed.pdf	23.7 KB	open | download	Andy	11/14/2006	Read message
Material.pdf	16.9 KB	open | download	Rolly	11/20/2006	Read message
white cliffs project engine.jpg	499.8 KB	open | download	grblake	06/30/2007	Read message
SV pickup.jpg	81 KB	open | download	Rolly	07/05/2007	Read message
112908ab.jpg	82.3 KB	open | download	Jeremy Holmes	11/29/2008	Read message
112908b1.jpg	87.6 KB	open | download	Jeremy Holmes	11/29/2008	Read message
Dieter engine.pdf	294.8 KB	open | download	Rolly	11/30/2008	Read message
Bryan Tractor.JPG	108 KB	open | download	Rolly	12/01/2008	Read message
Bryan Engine photos.jpg	84.6 KB	open | download	Rolly	12/01/2008	Read message
p1010002aa.jpg	36.4 KB	open | download	Rolly	12/02/2008	Read message
tractor1.jpg	136.6 KB	open | download	frustrated	12/02/2008	Read message
tractor2.jpg	111.8 KB	open | download	frustrated	12/02/2008	Read message
Tractor3.jpg	137.9 KB	open | download	frustrated	12/02/2008	Read message
tractor4.jpg	159.5 KB	open | download	frustrated	12/02/2008	Read message
tractor5.jpg	113.6 KB	open | download	frustrated	12/02/2008	Read message
tractor6.jpg	98.1 KB	open | download	frustrated	12/02/2008	Read message
071709a.jpg	77.4 KB	open | download	Jeremy Holmes	07/16/2009	Read message