L.T.D. with hi torque

[fullofhotair]

http://www.genuineideas.com/HallofInven ... ocker.html

I just found the solar rocker stirling engine. What if you pushed up a steel piston instead of water? The arched fall would produce a lot of torque. You could have these hammers in series. They would be stopped a few degrees over center, so the next fall would be in the right direction. The hammer would only grab the axel when it fell. Vertical solar troughs could focus solar heat on each hammer. The dwell time would be long at the trough and short on the fall. You could use helium as the working gas cause it’s totally sealed.

[fullofhotair]

I thought this would get some response. The only reason I brought it up was because I have never seen a stirling engine that didn't need a super large array of reflectors or lens to work using solar energy. That simple rocker stirling works by just using color contrast black and white. No it is not very efficient but even a helostat reflector would improve that, and shade on the other side. What I meant by high torque was any fallingweight attached to an arch has quite a lot of torque if you catch it mid way or closer to the bottom. Most LTD can barely carry their own weight. wouldn't this on a larger scale work to pump shallow water like those see saw oil rigs do. It's pretty low tech.

[vamoose]

Hey fullofhotair,

Thought it was an interesting idea but assumed someone else who understood it better than me might appraise it somewhat. I have played around with drinking birds, and incorrectly named radiometers, and other bits and bobs that could very loosely be called heat engines, but have never really seen what you described before.
Although, i can appreciate the concept you have raised, and had a bit of a search.
If you've got a crude kitchen table design in mind, maybe you could give it a shot. I would love to see the principle working. Even if it is just a proof of concept rig.
Are there any videos out there that show this design in action?

vamoose

[fullofhotair]

Vamoose, with a little research I found this engine not exactly the same, but it does use expanding gas to move a piston and works as a pump.The temp is in the range of 180f so its not a rankin cycle.It does use water as a cooling agent so it is kind of like a cross between the solar rocker stirling and the drinking bird.

http://thefraserdomain.typepad.com/ener ... heat_.html

The Energy Blog

June 12, 2007


Low Level Heat Powers Low Cost Hydraulic Engine
Deluge, Inc. has developed a thermal hydraulic engine that is now ready for commercialization. The company has just successfully completed long term field testing of the technology, and has obtained patents on the design in nearly 40 industrialized countries world wide.

The Natural Energy Engine™, requires no combustion, operates virtually silently, and generates no emissions. Developed over the past 10 years, it operates by utilizing low level heat energy, 180°F (82°C) is suitable for many applications, from solar, geothermal, or any other heat source, including waste heat from existing processes.

The main components of the engine system are quite simple – a piston/cylinder and a heat transfer system. The cylinder contains a piston and a working fluid, and depending on the application may have a module to reposition the piston after each stroke. The heat transfer system comprises heat exchangers, a system to circulate the heat transfer fluid (typically water), and a simple circulation controller.

The key difference between a traditional combustion engine and the NE Engine is that the NE Engine relies on the transfer of heat to, and its subsequent removal from, a working fluid within the cylinder. As the working fluid is heated it expands, providing the pressure to drive the piston, and is subsequently cooled to complete the cycle.

“It is a thermal hydraulic engine,” says Brian Hageman, the inventor of the Natural Energy Engine. “It uses the same principles of expansion and contraction from heat as a thermometer, and uses the expansion to create powerful hydraulic pressure in a manner similar to an automobile’s brakes.”

The Company projects that engine configurations can easily be priced at 60-85% of power systems that produce equivalent output.

The NE Engine creates mechanical energy in a three step process:

Step 1: Heated water is collected – for many applications 180°F is suitable.

Step 2: The hot water enters a heat exchanger where the heat is transferred to a working fluid. The working fluid, typically liquefied CO2, has a very high coefficient of expansion, meaning that it expands and contracts significantly, based on its temperature, while remaining in a liquid state. As the working fluid is heated, it expands, pushing a piston in the engine’s cylinder.

Step 3: Cooling water – generally in the range of 100° lower than the input water, with varying differentials depending on the application – then enters the heat exchanger causing the working fluid to contract, readying the piston for another stroke.

Proof of the engine’s operating principles was first demonstrated at the U.S. Department of Energy’s Rocky Mountain Oil Testing Center in Wyoming, where a prototype engine successfully pumped crude oil from underground formations using geothermal energy as the sole source of heat for operation.

In early 2006, Deluge embarked upon extensive field testing, conducting a multi-engine long term test under varying conditions in Kansas fields, and completed well over 100,000 hours of continuous operation over more than a year. The results exceeded even Deluge’s expectations in terms of reliability, costs, and performance.

[NerdyEE]

Are you thinking of the Minto Wheel? Google and YouTube to see some interesting contraptions...
-NerdyEE

[fullofhotair]

Ya Nerdyee, that is pretty much the idea. I think it could be improved by a helostat reflected on flat black and the condensing side shaded,The minto machine evaporates the propane so I think that makes it a rankine cycle.I think it takes more energy to cause a phase change than to expand a working fluid.So there is a possible efficiency improvement.It could make some simple little water pump, pond art.or aerate a fish pond,

[fullofhotair]

http://youtu.be/-fUlKBH1sY8
Vamoose, I finally found a good working model on ytube.thanks to Nerdyee.It looks like all kinds of improvements could be made to this engine.There was talk of valves being used,scaling it up and using the sun.Why not solar troughs to heat the working fluid? Could a regenerator be added? How about cooling the condenser other than ambient? Could the wheels be connected in series?

[NerdyEE]

All excellent questions FullOfHotAir!
Actually I was hoping you would find this link: http://www.youtube.com/watch?v=Za9td23Vk0c
Is it not big enough???
-NerdyEE

[vamoose]

OK fullofhotair and NerdyEE,
I must say those Minto Wheels look pretty cool.
After watching those videos, I can now see how they might have potential to produce some kind of power, especially if someone was able to refine the principles and design.

Could these wheels be considered a bunch of hand boilers on steroids?
http://www.youtube.com/watch?v=4eKxVRt1XT4
http://www.youtube.com/watch?v=cMy2fFeQMLM

So if a Minto wheel is a heat engine. Are some or many Stirling engine principles directly transferable, and if so what might they be..??

(some thoughts)
- To produce a wheel with a more stabilised torque/rotation, could you combine 2/3/or more (side by side) 'wheels' off the same hub, that are progressively radially 'offset' from each other.
- Use a flip/flop, gravity set valve, between chamber pairs, to prevent unwanted back flow.
- (use a MPPT on generator...????)

(why are so many cool things sent to distract us?)
vamoose

[fullofhotair]

Nerdyee & Vamoose, you two have a lot better understanding of this (Supercritical Fluid) is there any application for it here?
I think this type of engine has a lot of possibilities. Why does it have to be a wheel. The real force is in the pressures it builds up. All most 250 psi at slightly over 100f using Freon 11 as the working fluid. Wouldn’t that turn a turbine? A lot of models use a working gas which pushes a dividing piston that lifts water. Couldn’t the piston open valves at a high point on a vertical column letting the gas release, which is going to get mighty cold as it condenses. Keep your beer good and frozen. Another valve above the piston releases the heavy water, simply turning a pelton wheel or using the water hammer effect like a ram pump does. All to be reheated to rise and fall again in the heavy steel column.

[NerdyEE]

Hello FullOfHotAir!
Would your mechanism need seals? If yes, then from what **VERY LITTLE** I know about this stuff, it is not a match. As I mentioned to Blade, and I can’t discuss who/what I was involved with, but from what I observed and the video referenced in the “Supercritical” posting (http://www.stirlingengineforum.com/view ... f=1&t=1168), I do not see how one could possibly have a moving seal and retain any supercritical substance…

I am **NOT** an expert at this! Blade has made mention of Brayton Turbines and possibilities of a Ringbom SE using the stuff. Both are technologies that do not have or use sliding seals…
I do recommend you experiment. Even failure is a most satisfying experience!

Cheers,
-NerdyEE

[NerdyEE]

Vamoose!
Take a look at the Helios Project Continued and see how he increased the number of bulbs to make operation smoother, faster and more torque…
http://www.youtube.com/watch?v=bs_OtCsDJoY
I believe you are correct on the “HAND BOILER”. Or was the hand boiler just one section...
Still some mighty nice finds!!!
-NerdyEE

[fullofhotair]

Nerdyee, your way over my head on moving gaskets and such. I live on a small island and getting stuff to build anything is a real bitch. What I do want to build is a solar pump to make a water fall over a pond. The water has to move in the pond due to mosqitos. The other reason is I want to use it as a water chiller to cool the house.Cool temps at nite hot during the day.Ive saved up a ton load of old styrafoam to insulate it. I at first thought a stirling engine might work but some form of the minto wheel looks better and a nice water feature to boot.

[NerdyEE]

Greetings fullofhotair!

Most SE’s have rods that connect the piston & displacer to a crankshaft/flywheel (yes?). The piston & displacer have rings, seals, and/or dang small gaps to prevent compression/expansion losses. This is what I mean by moving seals…

How would you keep that stuff in your contraption???

I do not want to deter you from invention, but for your pond requirements, BUMPKIN had a great suggestion…

http://stirlingengineforum.com/viewtopic.php?f=1&t=1163
…NerdyEE, this place makes some of the aforementioned equipment, though in retrospect it looks like the technology depends more on pumps than controllers. I haven't looked too deep. http://www.sunpumps.com/ It's ironic in the investigation of Stirlings, that as I watch all those watts float up the chimney of my woodstove I have to limit computer time because my P.V.s are covered with snow. Bumpkin…

So the “Wheel” is looking better after all???
-NerdyEE

[fullofhotair]

When you said contraption, I didn’t know if you meant this one or my simple water pump.
#1 and #2 are one way valves set by timer or pressure. #7 is some sort of lock to keep the piston from moving until the cycle has completed. When the valve opens to release the Freon II at 250 psi or greater, it turns a #3 turbine that opens into an expansion valve which drops pressure and becomes a refrigerator. Copper coil collects the cold to cool freezer. The #3 turbine is where you really get your energy. It could be connected to a generator , water pump, or air compressor, etc. When the valves open, water falls to turn a pelton wheel (a little energy is recovered here).
The coil at the bottom circulates through a large parabolic solar trough using water or a higher boiling point liquid. #4The pelton could probably be used here to circulate the heating fluid . I am sure you would need good seals on the piston. Why couldn’t the piston become a linear generator by wrapping a copper wi re coil around the tall pressure column or would the thickness of a stainless steel pipe prohibit that?
After a second thought a water jacket at the top of the column below the piston could be opened after Freon reaches a certain high pressure to condense gas. Then drained dry when the pressure is low. The water would need to be drained later after the Freon has condensed below. Maybe you need two pistons X & Y one falls first on the condensed Freon, the second holds up the water till it has all fallen then is released. The final piston X would fall through the water,due to a one way valve to settle on the bottom piston Y.
If you meant the pond pump, I am still working on that. I like the idea of just a simple minto wheel maybe 4 ft diameter minto wheel made out of copper tubing and brass fittings using Freon and water. My problem is I am trying to cool my pond not heat it up to run the minto wheel. My heat has to be coming from some other place than the pond. Maybe a water trough just above the pond could be the heat source. A larger diameter bottom scoop water wheel made into the minto wheel would lift the water to a separate tank to feed the water fall. Or I could just use this device and run it day and night and just let perpetual motion do all the work. http://youtu.be/-KtFZMN7_Bw