i problem has linearly varying heat flux at the wall(flux a function of x co ordinate only) i have written the udf but it gives 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 udf program is as folows

#include #DEFINE C1 39682.5 #DEFINE C2 2645502.646

DEFINE_PROFILE( heat_flux,thread,i) { real pos_vec[ND_ND]; real x; face_t f; begin_f_loop(f,thread) { F_CENTROID(pos_vec,f,thread); x=pos_vec[1]; F_PROFILE(f,thread,i)=C1 - C2*x; } end_f_loop(f,thread) }

please help me thanks in advance

You are using a big weapon on a small problem. Heat flux boundary condition varying along x coordinate can be applied by boundary profiles instead of UDF. Read the fluent user's guide for further details.