Fluent error help needed

Praveen

I have been trying using the udf coded by my friend for fluent 6.1 in fluent 6.2 and getting the error. 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: ()

I have seen similar questions but did not see any satisfactory replies. I am pasting the udf here. and a brief definition of the problem to be solved.

I need to model natural convection using boussinesq approximation in a tank which has water and is heated by the solar radiation.

The first sub function .ie EXECUTE AT END to calculate the average temaperature of the plate. It takes the temp of each thread in the mesh and cumulates the product of the area and temp. The area weighted average temp is given by the ration b/n the product and total area ie wt_temp.

The second function ie DEFINE_PROFILE is to find the heat flux at that temp, and time of instant. It is basically giving a for loop with the heat flux function to calc the heat flux value for the variable of time and temp.

As such there is nothing wrong in the code as it had worked for fluent 6.1. It would really great if someone coyuld help me out.

/* User Defined Function for considering the variable heat flux function with heat loss*/ #include"udf.h" #include"mem.h" //#include<math.h> Domain *d; Thread *tf; face_t f; real wt_temp=298.0; DEFINE_EXECUTE_AT_END(facetemp) { real area; real av[2]; wt_temp=0.0; area=0.0; d= Get_Domain(1); tf = Lookup_Thread(d,8); begin_f_loop(f,tf) { F_AREA(av,f,tf); wt_temp += NV_MAG(av)*F_T(f,tf); area += NV_MAG(av); } end_f_loop(f,tf) wt_temp /= area; printf("Temp %.4f",wt_temp); } DEFINE_PROFILE(unsteady_heat_flux, t1, pos1) { begin_f_loop(f, t1) { real t = RP_Get_Real("flow-time"); if (t<=39600.0) { if (t<32400.0) F_PROFILE(f,t1,pos1)= 750*sin(3.14*t/39600.0)-2.03*(wt_temp+ 4.0*pow(10.0,- 13.0)*pow(t,3.0)- 2.0*pow(10.0,-.0)*pow(t,2.0)-0.00005*t-298); else F_PROFILE(f, t1, pos1) = 750*sin(3.14*t/39600.0)-2.03*(wt_temp- 2.0*pow(10.0,-14.0)*pow(t,3.0)+ 2.0*pow(10.0,-9.0)*pow(t,2.0)+0.0002*t-321.6); } else F_PROFILE(f,t1,pos1)=0-2.03*(wt_temp-2.0*pow(10.0,-14.0)*pow(t,3.0)+ 2.0*pow(10.0,-9.0)*pow(t,2.0)+0.0002*t-311.52); } end_f_loop(f, t1) printf("\n Temp %.4f",wt_temp); }

Thanks in advance.