[mateus]

Hi,

I need to write an UDF where velocity gradients in current and previous timestep are included.

As far as I understand gradients from previous timestep cannot be called directly (like for the current time - for example C_DUDX(c,t)). I guess the easiest way (the only way) is to use velocity from previous time step (C_U_M1(c,t)) and calculate the gradient... But I cannot find a macro for the cell size... and also what happens when I use unstructured mesh?
Where is it written how Fluent calculates the velocity gradient?

Thanks,
Mateus

[rasoulb]

Hi,
I have the same problem in my UDF and I need Velocity gradient in previous time step. if you find solution for this problem please help me.

thanks