Inventor wizard 6 Cyl Radial

Discussion in 'Plans' started by Jmccrack, Sep 25, 2018.

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  1. Sep 25, 2018 #1

    Jmccrack

    Jmccrack

    Jmccrack

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    Hey All
    I have spent the last few months building the 6 Cylinder Radial Pneumatic Engine. After assembly it will not run. So I started to try and analyze what the problem may be. I think it is in the air valve configuration. The crank has an offset pin that move a valve eccentricitly over a set of holes. As air is injected into the valve the therory is it pushes one pisrion down which exposes another port to the next piston on so on. After a “million hours” of machining I find that actually 3 ports are open at the same time. So air is trying to get into 3 cylinders at the same time. So in my opinion the drawing is wrong and I am not sure if there is a fix for it.if this is the case I would caution against using Inventor Wizard unless you have vetted the drawing completely. If there is anyone out there than can help I would greatly appreciate it. Below are some photos of what I am talking about.

    upload_2018-9-25_10-32-28.png


    upload_2018-9-25_10-40-42.jpeg

    upload_2018-9-25_10-41-28.jpeg

    upload_2018-9-25_10-42-37.jpeg

    Any thoughts would would sure help
     
  2. Sep 27, 2018 #2

    rweber

    rweber

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    Is that brass-part in the 3rd picture that one from "Valve.pdf"? Looks different to me.
     
  3. Sep 27, 2018 #3

    Tim1974

    Tim1974

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    Really hope you sort it out I did the vertical Stirling had not to many problems but that’s not the best sight for there plains I beleave all unproven? I would not recommended also
     
  4. Sep 27, 2018 #4

    Jmccrack

    Jmccrack

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    Yes the brass part is the valve pdf. I machined out the sectors to see if more than one power port was open at the same time. And indeed at tdc 3 are open. So when air is injected that should only drive that piston down the ports on either side are open as well. I triple checked my dimensions and they are right. It should be a very simple design. One hole opens drives the piston down and vents moves the crank around to expose the next hole and so on.
     
  5. Sep 28, 2018 #5

    rweber

    rweber

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    Ok, now I see. You are right, this cannot work. I would suggest moving the valves excenter a few degrees (30?) forward in spinning direction compared to the crankshaft. This assymetry would cause in sum more pressure in the down-moving pistons than in the upmoving.
     
  6. Sep 28, 2018 #6

    Jmccrack

    Jmccrack

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    I will give it a try tks
     
  7. Sep 29, 2018 #7

    ally-oop

    ally-oop

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    Aircraft radial engines altho mostly 4 stroke just NEVER have even number of cylinders,..a similar problem with valve timing,..
     
  8. Oct 1, 2018 #8

    nel2lar

    nel2lar

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    That is one beautiful design with the square cylinders. I was wondering if you about the heat and just how hot it would become with the limited ventilation. There is not a lot of air coming of those spokes, I was just wondering if you give it any thought. I must say it is a sharp design being square.
    Looks sometimes trumps.
    Nelson
     
  9. Oct 11, 2018 #9

    mohavegun

    mohavegun

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    I would check the timing, an air engine would require valves to be open for most of the down stroke of the piston and the exhaust valving must be open for most of the up stroke of the piston. I would seriously expect to see three intake and three exhaust valves open at the same time. I would NOT expect three valves open on pistons that are not moving in the same direction, that is the valve timing would be a WAVE of air traveling around the engine followed by a wave of exhaust valve openings. As for comparison to a 4 cycle internal combustion engine, the number of cylinders has does not matter because there is NO compression / power stroke with closed valves. Each piston\cylinder gets a "power stroke and exhaust stroke" per revolution. I am fascinated with the simplicity of the design, your work looks very good!
     
  10. Oct 12, 2018 #10

    popnrattle

    popnrattle

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    here is the 6-cyl radial air engine. later, rt.

     

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