UDF, velocity withinh the domain
 

Hello.

Thanks for your interest in reading my question.

For post-processing of my problem, I need to draw a LINE and use a UDF to extract the values of velocity at the faces of the line. I did this though Define_adjust and used loop to go over all the faces and pick the faces that I want. But when I use F_U(f,t) it gives the following message:

Error: FLUENT received fatal signal (ACCESS_VIOLATION) 1. Note exact events leading to error. 2. Save case/data under new name. 3. Exit program and restart to continue. 4. Report error to your distributor. Error Object: ()

My question is how can I access the values of velocity at those faces? I looked into the manual and it says that F_U(f,t), F_V(f,t), F_W(f,t) and F_T(f,t) are just for boundaries.

Thanks, Mazyar

Re: UDF, velocity withinh the domain
 

you can try the marco DEFINE_OnDemand. This marco help you deal with data after you finish computation.

Re: UDF, velocity withinh the domain
 

Face values for interior cells are not stored so F_U(f,t) wont work. You will have to calculate the face value from the adjacent cell values. As a first estimate you could use the averadge F_U=(C_U(c0,t0)+C_U(c1,t1))/2.

RoM