Solved the oil issue on this concept

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Sockmonkey, Aug 21, 2019.

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  1. Aug 21, 2019 #1

    Sockmonkey

    Sockmonkey

    Sockmonkey

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    So, a while back I posted this guy.
    [​IMG]
    A three-cylinder air cooled radial diesel two-stroke. Kept it to only three cylinders so it could have stroke overlap while using nested forked con rods to prevent the off-axis thrust and balance issues radials using a master rod have.
    There was a potential issue with lubricating the rings without losing oil as it's meant to have four-stroke type crankcase lubrication with no oil mixed with the fuel.

    [​IMG]
    Putting oil channels running up the crosshead rod to radial channels in the piston head that open out between the piston rings solves the piston lubrication issue and helps cool the piston.
    Preventing leakage was done by getting rid of the side bulge transfer ports in favor of a central piston valve covering a ring of holes in the piston head, allowing the fresh air charge into the top chamber of the cylinder. As it's a two-stroke, the valve cam can be right on the crank, and one cam lobe can actuate all three piston valves. The overhead exhaust valves will still need rockers and lifters, but that's not too bad as we still don't need a separate camshaft.
    I think everything is covered.
    Anyone spot anything I missed?
     
  2. Aug 22, 2019 #2

    proppastie

    proppastie

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    There probably is a lot of engineering left to do ......pretty pictures and gif though.
     
  3. Aug 22, 2019 #3

    pictsidhe

    pictsidhe

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    Yes, you need to work out how you're going to actually build it.
     
  4. Aug 22, 2019 #4

    Sockmonkey

    Sockmonkey

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    Anybody got a machine shop I can borrow?
    Otherwise I'm limited to what I can cobble together out of cans and wire.
     
  5. Aug 22, 2019 #5

    dmar836

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    I don’t get it. Are you just trying to add volumetric efficiency with transfers and a valve train? The crank case volume is yuge so...
    Dave
     
  6. Aug 22, 2019 #6

    Sockmonkey

    Sockmonkey

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    It's not using crankcase scavenging. The bottom half of the cylinder is used for that. The valves are to give it uniflow scavenging without the oil leakage that can happen with ports.
     
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  7. Aug 23, 2019 #7

    pwood66889

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    I like it... And hell, it might even work! Perhaps a one-cyl. proof of? No, I don't do machine work.
     
  8. Aug 23, 2019 #8

    TFF

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    So with the intake under the piston, is that chamber going to have a one way valve so when the piston moves down, it’s not going to pump the air backwards out the intake, or is the valves in the pistons to be so free flowing that it’s almost transparent when the piston goes down for the intake stroke? Supercharged?
     
  9. Aug 23, 2019 #9

    Sockmonkey

    Sockmonkey

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    Right, the lower piston chamber would use a reed valve for intake, and an actuated poppet valve to transfer the scavenging charge from the lower area to the upper. It's not supercharging, but a turbo could be added for more power.
     

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