Wall Shear Stress/ Surface Cf LIC in Ensight

- March 10, 2024 at 10:24 pm
  
  Amogh Kulkarni
  Subscriber
  
  Hello, I am new to Ansys Ensight and trying to plot wall shear stress vector LIC in Ensight over a wing(no slip condition). I am following this ensight tutorial video; it doesn't show how to calculate the wall shear stress vector which I need help with. I have tried to play around with the predefined functions (such as BL_CfTau) to create a scalar quantity variable. I am not sure whether the scalar quantity is correct. How can I calculate the WSS vector field to plot surface LIC? Any ideas or recommendations would be of great help.
- March 12, 2024 at 3:59 pm
  
  CFD_Friend
  Ansys Employee
  
  Hi Amogh,
  The wall shear stress is inherently a scalar quantity because it represents the magnitude of the force per unit area acting parallel to the surface.
  
  And LIC in Ensight only works for vectors. BL_CfTau will return a scalar variable, not a vector.
  To plot surface LIC it is better to use a velocity vector as it gives a better representation of flow directions. A surface offset of 0.01 would be suitable.
  - March 12, 2024 at 7:11 pm
    
    Amogh Kulkarni
    Subscriber
    
    Thanks for the answer, then what vector field is displayed as WSS LIC in the tutorial? We can see that in the tutorial a nonzero surface variable is chosen named wall shear stress, it might be a calculated variable. Wanted to know how to go about that.