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Thread: Engine Design

  1. #1
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    Engine Design

    I have an attachment for my engine design. It says top torus, but they are both half spheres or half hemispheres. It seems counterintuitive, but the explosion at the base of the closed cylinder doesn't just blow past the cylinders, but pushes them apart. The x's lining just below the cylinders as well as the shape of the hemispherical cylinders drives a pure flame as opposed to the usual combustion in a cylinder of dispersed cloud. It appears that the engine would be opposed force because the pistons are moving left and right, instead of up and down? That's my question. The top of the cylinder is open to the atmosphere, and the flame disintegrates to a string there.
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    Administrator Kelly Bramble's Avatar
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    Do a you have a geometric mathematical proof for "the explosion at the base of the closed cylinder doesn't just blow past the cylinders, but pushes them apart. "?

    You need to expand on the physics explanation and evidence to move forward..
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    In the phase, or phase space, of the evolution of the combustion, it looks like beneath the cylinder at combustion a cross section of a torus, but what is actually a nonlinear oscillation that looks like this: https://www.google.com/search?q=osci...qgtdkG79s11qM:
    So it is a nonlinear oscillation that produces the flame pattern.

    I went to the link and it mentions a double well structure. The flame itself produced between the two hemispheres looks like a double cone, that looks like this: https://www.google.com/search?safe=s...QDgFxUKFLSFqM:

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    Administrator Kelly Bramble's Avatar
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    This is not a mathematical proof of the concept. You need to model the physics and associated math... I don't think you're conceptually understanding the acting pressures correctly...

    Quote Originally Posted by jason_buford View Post
    In the phase, or phase space, of the evolution of the combustion, it looks like beneath the cylinder at combustion a cross section of a torus, but what is actually a nonlinear oscillation that looks like this: https://www.google.com/search?q=osci...qgtdkG79s11qM:
    So it is a nonlinear oscillation that produces the flame pattern.

    I went to the link and it mentions a double well structure. The flame itself produced between the two hemispheres looks like a double cone, that looks like this: https://www.google.com/search?safe=s...QDgFxUKFLSFqM:
    Tell me and I forget. Teach me and I remember. Involve me and I learn.

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    Technical Fellow jboggs's Avatar
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    Its not the flame itself that pushes the cylinders in an engine, its the pressure from the expanding gases. Pressure is non-directional. It acts equally in all directions. In an internal combustion engine, the gases are captured inside a volume in which there is only one movable surface, the top of the piston. They build pressure inside that closed volume until that pressure overcomes the resisting force of the piston. The piston then moves - because it is the only thing that can move. If the gases had some other available exit they would not build up pressure, and the piston would not move at all. In your scenario, (if I understand it) the expanding gases of the flame can escape out of the top. They will create no pressure, which means they will not move the pistons.

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    Well, the half hemispheres don't just join at the tip, the curve is much more flat for a bit where it touches. The flame part was just to show, during build up of pressure, the gases don't collect in messy clumps, so it's more efficient. If you can imagine a tube with two half hemispheres just touching that require great force to move, during pressure build up, what can move will move, and having the gases escape out the top I'm just guessing must halt the build up of inefficient clumping of gases during compression, so it would be as probably efficient as an engine could get. Honda's new 2-stroke or 2-cycle engine, if you look at their patent drawing, has a rounded curve in the cylinder itself that looks like the inside of a torus, similar to the curve -between- these two left-right cylinders, and honda's produces a relatively non-clumping combustion (there is a central sphere in the flame, but still has a messy cloud around it).

    Also, the gas is injected below the two half-hemisphere pistons, in the bottom of the cylinder, and none in the top of the cylinder.
    Last edited by jason_buford; 08-27-2017 at 05:41 PM.

  7. #7
    Administrator Kelly Bramble's Avatar
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    Have you modeled the combustion in any CAE software. Like ANSYS Combustion modeling software?


    Quote Originally Posted by jason_buford View Post
    Well, the half hemispheres don't just join at the tip, the curve is much more flat for a bit where it touches. The flame part was just to show, during build up of pressure, the gases don't collect in messy clumps, so it's more efficient. If you can imagine a tube with two half hemispheres just touching that require great force to move, during pressure build up, what can move will move, and having the gases escape out the top I'm just guessing must halt the build up of inefficient clumping of gases during compression, so it would be as probably efficient as an engine could get. Honda's new 2-stroke or 2-cycle engine, if you look at their patent drawing, has a rounded curve in the cylinder itself that looks like the inside of a torus, similar to the curve -between- these two left-right cylinders, and honda's produces a relatively non-clumping combustion (there is a central sphere in the flame, but still has a messy cloud around it).

    Also, the gas is injected below the two half-hemisphere pistons, in the bottom of the cylinder, and none in the top of the cylinder.
    Tell me and I forget. Teach me and I remember. Involve me and I learn.

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