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dqsis / parsec-airfoils

Generate and plot the contour of an airfoil using the PARSEC parameterization
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insufficient resolution #2

Open MaNyh opened 2 years ago

MaNyh commented 2 years ago

i implemented your version of the parsec-aifroils into an automatation library for cascade-simulations. as the library is also suitable for large eddy simulations the quality of the airfoil-pointclouds is pretty important

we don't seem to have an option for TE's with a rounded shape. and at the LE the resolution is pretty coarse (area of high curvature).

MaNyh commented 2 years ago

in my implementation of your code i solved the issue using a halfsinespacing-method. in case i will have time i will make a merge-request in your repo. but i also assume you can implment this method on your own?

i got the idea for this from:

https://github.com/dgorissen/naca

    beta = np.linspace(0.0, pi, res)
    halfsinespacing = [(0.5 * (1.0 - np.cos(x))) for x in beta]
    xx_pre = np.array(halfsinespacing[::-1])
    #xx_pre = x * np.linspace(xte, xle, res)
    yy_pre = (cf_pre[0] * xx_pre ** (1 / 2) +
              cf_pre[1] * xx_pre ** (3 / 2) +
              cf_pre[2] * xx_pre ** (5 / 2) +
              cf_pre[3] * xx_pre ** (7 / 2) +
              cf_pre[4] * xx_pre ** (9 / 2) +
              cf_pre[5] * xx_pre ** (11 / 2)
              )

    # Evaluate suction (upper) surface points
    #xx_suc = x * np.linspace(xle, xte, res)
    xx_suc = np.array(halfsinespacing)
    yy_suc = (cf_suc[0] * xx_suc ** (1 / 2) +
              cf_suc[1] * xx_suc ** (3 / 2) +
              cf_suc[2] * xx_suc ** (5 / 2) +
              cf_suc[3] * xx_suc ** (7 / 2) +
              cf_suc[4] * xx_suc ** (9 / 2) +
              cf_suc[5] * xx_suc ** (11 / 2)
              )
MaNyh commented 2 years ago

... and there is still the issue, that the TE is in any case pointed and not rounded... i will also look for a solution for this