Liquid piston stirling pump

[windstuffnow]

  I spent most of yesterday scrounging parts and this morning it took all of 15 minutes to put it together.  Stuck it in a can of water, used a propane torch to warm it up and off it went...

  Its just a small one, stands about 14" tall.  The "U" has 30" of 1/2" od soft copper tube.  The connector at the top is simply some plastic 1/4" tube shoved on some barb fittings at the top of the "U".   With such small tubing its not a blast pump by any means, probably only 3/8" inside diameter so it make for some very small power pistons.  It takes about an hour to pump 1 gal of water from one bucket to another lifting the water about 7 or 8 inches.  Still can't locate my other one, it was a bit larger than this one made of larger diameter tubing.

  The check valves are from 2 old coffee makers, one still works real good and the other has a bit of a leak but holds enough to keep the pulse going.  It was those or a couple PCV valves I had laying around from some old chevy's.  

  I guess all that needs to be done now is make a stand for it and toss it in the corner for future reference.

   Next, liquid piston rings...

Have Fun

Windstuff Ed

[stop4stuff]

nice one Ed )

i found another example via google earlier today...

http://www.maxpie.de/Fluidyne.htm

paul

[nothing to lose]

Thanks. Thats alot different than I had pictured it in my mind from the sketch.

Now on that hot side, is that an open pipe in the T connecting the two, water pipe and heat pipe, together? For some reason I had it pictured as the cross pipe being smaller and sticking inside the hot pipe capped off.

PVC valves eh, I hadn't thought of those before either for one way valves. I bet they would work for alot of things.

[windstuffnow]

   If you mean is the "T" open to the pump and engine the answer is yes.  The pressure developed in the cycle pushes water out, once the pressure drops it draws fresh water in.

   I was reading about another one that used 1.75" tubing for the top two uprights and a 2.5" connecting tube at the bottom.  The pump was done in 1" tubing.   The uprights were both 10" tall, the connecting tube was 24" wide.  A heat exchange was built on the cold side to allow cold water to flow around the cold side tube.  This one was said to pump 400 gallons per hour.  Another which is still being made in India, a company called Metal Box Co. of Calcutta is producing one that pumps 2500 gal of water per hour at a head of 10 ft.

   None of these machines are very efficient ranging around 4-7% efficiency but if you have a waste heat source anyway its still a bonus.

Have Fun

Windstuff Ed

 

[windstuffnow]

   Thats one I've never seen.   Nice diagrams, makes it easy to understand.  I used to subscribe (and collect) the stirling newsletter produced by Andy Ross's brother... Stirling Machine World. http://www.stirmach.com/  They always had different versions of all kinds of machines being tinkered with.  I have several years of the publication in boxes somewhere... have to dig them out again.

Have Fun

Windstuff Ed

[iFred]

Could this be used as a pump for replacment of a "heat pump" ?

It seems it could be scaled up and would eb cheaper to run and the volume to pump would be ok??

[windstuffnow]

  I was doing some searching through the patent database and found my idea for the liquid piston rings has already been patented... Thought I had something original.  Its called a plunging cylinder Liquid piston stirling engine.  Patent number 4,676,066 .   What ever you think up, its surly been thought of before ;o)

   Anyway its quite interesting, The patent claims at a temp difference of 120 degrees F, a 36 inch stroke and 2 36 inch pistons can produce as high as 30 kw at 120 rpm.   A 36 inch piston at 3psi would give you about 3000 lbs of push against an arm of 1.5 ft comes out to around 4500 ft lbs of torque.   Most likely, once in motion including losses you'd end up with 1/2 that or much less.  Probably not super efficient but if it was solar or wood heated could have some potential...

 still plan on making a model of it to see how it works....

Just having fun as usual...

Windstuff Ed

[ghurd]

More on steam than Stirling.

Could this funtcion as a higher pressure 'flash pump'? Just coined it maybe.

Move the in/out pipe to the top. Do away with the cold side, or make it a very small ID.

The hot side would boil. Great expansion and pressure if need be, pushing the water up. The steam would move out the in/out tube and cool, condensing, and bringing up more water.

I know nothing about steam, so I figure this is dangerous, won't work, or is common.

Thought it could be interesting.

And wouldn't this be great for a wood/coal fired passive radiant floor heater!

G-

[Norm]

I guess all that needs to be done now is make a stand for it and toss it in the corner for future reference.

(my personal experiences) Did you ever do that and couple of years wonder how you made it or what it was? ? ....LOL !

             ( :>) Norm.

[Norm]

....or unless you label everything like 'Batman & Robin' do in the 'Batcave'

       ( :>) Norm

[bob golding]

hi ed , looking at that patent makes be want to jump up and make one .. now. but its dark cold and i am in bed so better wait till  daytime. thinking  oil drums  for the cylinders on the big one. maybe use  old 600 gallon orange juice tanks for the containers. certainly could be made  using  cheap  second hand bits. wondering how it  would conpare with a  minto wheel?

bob

[bob golding]

at least ith mechanical things you  might be able to work out what it was. doesnt work with half finished  electronic projects. maybe we should have a  competition of everyones unidentified "things"

bob

[windstuffnow]

   I pretty much had it figured out then I just had to go snooping around.   I was a bit depressed when I seen the patent although its nice to know in advance that it could work.  I read a partial document from a group that did some testing based on his patent and apparantly it scales up nicely.  If a small one runs at 100 rpm the scaled up version will do the same.  Unfortunately, a machine with 2 55 gal drums as pistons would take up a very large area in my shop and the liquid would have to be either oil or antifreeze mix... pretty expensive piston rings although much cheaper than machining a piston, rings, and cylinder for that beast.  It sure would be fun to watch it run though... I would imagine it would produce much more power in the winter...

Lots of fun!

Windstuff Ed

[windstuffnow]

  Norm

   I'm a major pack rat, nothing gets thrown out.  Your right though, I should label everything.  All my failures get tossed in a pile for recycling into other projects at a later date.  Its quite possible I needed some cable ends and used the tubing from the other liquid piston engine, or maybe it was for the eddy current heater experiment, possibly using a piece of it to repair my air line when I accidently burned a hole in it while welding, It might be part of the stupid little pulse jet engine I nearly blew my toe off... or...

I only have one interest... everything!

Windstuff Ed

[nothing to lose]

"   If you mean is the "T" open to the pump and engine the answer is yes.  The pressure developed in the cycle pushes water out, once the pressure drops it draws fresh water in."

Thanks that's what I meant, I thought so but wasn't sure as I could think of another way it could be built where the hot water was just in contact with a sealed tube part of the time and not at other times maybe, which probably would not worked anyway. I confuse myself too much.

I just raised my first NON_WORKING mill today too! Pics later of what not to build!!

 I just need better blades.

I'll probably be at the hardware store today, I'll look around here before I go and see what I have already and what I need to buy still to build one of these. Maybe I can build a working one this evening.

Something I am wondering about though, it has been mentioned a few times about maybe using one to pump water for hot water heat and such. Would this work? I am thinking it won't. Isn't it more pumping the cold water from the supplie tank than actually heating and pumping hot water? Also if you had a hot water source tank, then wouldn't using hot water to begin with slow or stop the engine? Or would that actaully make it run better since it would already be hot and only need bumped up a few degrees? Any advice on pumping hot water?

I was thinking of trying this on my charcoal maker to move hot water and also others have mentioned similar use, I just occured to me to ask about it though.

In your other post about these someone asked about pumping water up hill and letting it run back down to power a water wheel. Something else I had thought of also for the charcoal maker system maybe using several or many of these at once. If that bigger one you mentioned is supposed to move 400 gal an hour, then I think maybe that would work.

 Use several if needed to just pump into a container and let run backover a wheel and into the source container again. Sort of an open closed loop? Think that would work if a person had the heat already, or using solar?

[windstuffnow]

  ntl,

    I don't think pumping hot water would be a problem.  You may have to externally cool the cold side to maintain a reasonable temp difference.

    As far as pumping water to fill a tank and using it to run a generator would most likely work also.  As long as the energy your putting into it is free.  Like I said before these things are only 4 to 7% efficient so 93% of what you put into it is lost.  If you had an abundant solar site you could store the pumped water for either nighttime use or for cloudy days.  

    My thoughts on the device were for simple tasks, such as circulating water through a heat exchanger for domestic hot water and the pump would be driven from the waste heat in the chimney.  Simple, cheap and functional.  Water storage for power can be costly if you factor in the tanks and plumbing as well as the pelton wheel and genny.  There may be better, cheaper ways to store the energy.

    I'm sure there are alot of ways to put a device like this to work but its good to look at all the alternatives...

Lots of fun in any case

Windstuff Ed

 

[nothing to lose]

Thanks again.

Yes, free heat is what I am thinking for a water wheel using this pump if I could get around that 400gph or maybe 800 using 2 of them etc... In winter I could use the excess heat for house heating, green house or many other things maybe from the charcoal maker. Durring the realy hot summer though not alot of use for heat so I would otherwise be throwing most of it away probably. If maybe I could use this water pump to either make electric or drive a pump I could store the gas from the charcoal maker in propane tanks maybe to use latter when not making charcoal. Use the water pump when heat is available and the gas other times.

I hope to get all the parts today and build this tonight.

I am making my list and checking it twice

.

[ghurd]

I have piles of little circuits in the basement.

I'm sure they all work, or I would have kept going til they did, or torn them appart.

I have no idea what most of them do.

G-

[nothing to lose]

Well, another defeat!

Went in town to just buy everything to build this with.

About $3/foot for tubbing, $1+ each for T's, $5 each for the cheapest check valves. I was in about $20 or better before even getting to the top caps barbed fittings etc..

I have plenty of copper tubbing, I was told it's refrigeration tubbing and they don't have anything to fit it.

Well looks like I'll be casting my own parts from pewter like check valves, and I geuss  brazing pipe together instead of using normal fittings.

Not a problem, just not a quick 15 minute one for me I geuss

 I'll look for parts around here tonight and tommorow and see what I have. I figured about $10 for everything new, geuss it's been awhile since I bought anything!!