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Hoping to verify valve specs

  1. Apr 20, 2010 #1
    Ok, so I'm building a pneumatic gun with a barrel 0.3m long, operated using air pressure. The barrel is square, 1cm on each side, and the projectile is a 5g elongated cube. I wrote some code in mathematica to plot the speed in m/s versus the air pressure in psi.

    I was wondering if anyone could verify that my calculations are accurate, and if not, where I may have gone wrong. I'm pretty confident, but as I'm spending money on this I want to be sure.

    The mathematica code is below:

    -------------------------------

    (*Variables;
    x is the distance over which it accelerates;
    m is projectile mass in kg;
    area is area that the force acts on in cm (square barrel 1cm on each \
    side);
    *)

    x = .3;
    m = .005;
    area = 1;

    (* Constants and conversions *)
    psiToPascalsConstant = 6894.7573;

    pressforce[pressure_] := (pressure*psiToPascalsConstant)*
    area; (* gives N *)

    velocity[force_] := ((force/m)*Sqrt[(2 x)/(force/m)])/100;

    Plot[velocity[pressforce[psi]], {psi, 0, 150},
    AxesLabel -> {Psi, Velocity}]

    -------------------------------

    Thanks for your help!

    -Axemaster
     
  2. jcsd
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