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Solar powered sterling engine

  1. Oct 3, 2007 #1
    would a stirling engine work under the heat of 1000 2" x 2" spots of sunlight directed at a single point on its surface? (the point will be a 2" x2" square) and do you need some sort of coolant to lower the heat of the gas you use?
    Last edited: Oct 3, 2007
  2. jcsd
  3. Oct 4, 2007 #2
    A Stirling engine will work from the heat off of the palm of your hand. You dont get much useful work off of it though.
  4. Oct 4, 2007 #3
    i understand that it will work from any heat souce but the air will eb be extreamly hot in it and will it have time to cool sufficiently before it reenters again? with jsut a pipe with like heat sinks of do i need water running to cool it?
  5. Oct 4, 2007 #4
    ok and where might a get the materials to make a sterling engine that could withstand enough heat to turn a plate a steal bright red. or turn a pop can into smoke.
  6. Oct 5, 2007 #5


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    You could get the materials from a scrap yard, a plumbers' merchant, DIY shop or similar.
  7. Oct 15, 2007 #6
    ok then i ahve been lookign around for effective ways to build a sterling angine but i cannot seem to find anythign reliable. any ideas?
  8. Oct 15, 2007 #7
    At 833 watts per square yard available how many watts do you see going on that 2x2 plate? From there it's an engineering problem. You might want to flow some fluid such as oil with a dark pigment and then risk heat loss when moving it to the stirling.
  9. Oct 15, 2007 #8
    ok then i wold be getting approx-33.32 watts per 2" x 2" plate. and considering i lowered the # on mirrors to about 850 il be getting 28322 watts focused onto a 2" x 2" area.

    I managed to figure out how to construct the engine
    Another concern of mine is what could i use as a lubricant? i am going to be using regular air and i cannot use oil as a lube because of the chance of it lighting on fire under the heat.

    and using oil as the fluid would definitely not work to high of a chance of it lighting in heat piston chamber (I do not think i will be able to remove all the O2 from the chambers as well and do not think oil would expand and contract to what i need)
    Last edited: Oct 15, 2007
  10. Oct 15, 2007 #9
    34 square yards focused on a 2inch square plate. I brought up the pigmented oil as a way to transfer heat to the medium. Put black ink in a cup of water and focus the suns rays with 2 or 3 inch magnifying glass on the surface of the liquid. Instantly the steam generated is condensed and a wisp of water is emitted from the focal point. Point being you do not have to heat the entire mass to make steam. Now you have to figure what to do with it before it cools.

    I take it you are not going with a lubricated freon like a car's for the working fluid.
  11. Oct 15, 2007 #10
    no i am not. I would be using air, oxygen free air, or nitrogen. I will be using a 2 cylinder engine and have plates of metal sticking out of the "cold" cylinder with water running through them to cool the gas.
  12. Oct 15, 2007 #11
    my engine will look similar to this diagram-

    Attached Files:

  13. Oct 15, 2007 #12
  14. Oct 15, 2007 #13
    i have spent much time on wikipedia an the Stirling engine page and related articles and pages. and the image is on the url-
    http://blog.steamshift.com/wp-content/uploads/moved/stirling_engine.gif [Broken]

    but my main question is do i need a lube and if i do what could i use that can withstand high temperatures and not ignite.
    Last edited by a moderator: May 3, 2017
  15. Oct 15, 2007 #14
    Yes I see it now. Silicon Carbide was attempted as an engine block by Smokey Yunick, but he said it was a ***** to machine. Could take a lot of heat with minimal dimension change thus negating the need for a radiator in his car engine application.

    As for your lube questions I have to say I am out of my pay grade. Maybe on the engineering section on materials help might come.
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