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Prandtl-Meyer Function Iteration

  1. Apr 7, 2009 #1
    hi.. i'm trying to write a matlab code that will iterate the mach value given a certain value for nu.

    nu = sqrt((gamma +1)/(gamma -1))*atan(sqrt((gamma - 1)/(gamma +1)*(M^2-1)))-atan(sqrt(M^2-1))

    this is the equation for the prandtl-meyer function, but how do i write it in matlab so that i can extract the value of nu for a given M value? sort of like the goal seak function in excel...

    i would appreciate anyone's help!
  2. jcsd
  3. Apr 8, 2009 #2
    I don't know of any built-in MATLAB function that does this for you (without any additional toolboxes, that is), but that doesn't mean there isn't one...

    I would look into something like the Newton-Raphson's method (but there are many others). The wikipedia article on Newton's Method is pretty good, and at the bottom is a list of similar algorithms. It's not difficult to write some algorithm like this for MATLAB.

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