Hi! I am trying to calculate Wall Shear Stress from 2D PIV data. I have the following scalar data for my mesh:(x coordinate, y coordinate, x component of velocity, y component of velocity). I have calculated a simple velocity magnitude using sqrt(Vx^2+Vy^2). I read that you should be able to calculate a velocity gradient and multiply by normals and viscosity to get WSS, however I get all 0 values when I do this. Could someone walk me through how to calculate WSS using this data?

Also, is there a way that I can convert the scalar Vx and Vy data into true vectors so I can use it to orient my 2D glyphs? I’m very new to paraview, so any help is appreciated. Thanks!