[pranab_jha]

Hello All,
Can someone tell me what am I doing wrong in this UDF that I have? I want to have a pressure inlet boundary condition with decreasing pressure as I march in time.


/************************************************** ********************
pr_10.c
UDF for specifying a pressure boundary condition
************************************************** ********************/

#include "udf.h"

DEFINE_PROFILE(pr_10, thread, nv)
{
face_t f; /* Defines f as a face thread index */
real t = CURRENT_TIME; /*current flow time*/
real dt = RP_Get_Real("physical-time-step");
real vel = F_V(f,thread); /* v-velocity*/
real Q0 = 5.0; /*Q0=l*b*h, l=b=1 */
real Q;
real newQ;
real rho = 0.6679; /*density*/
real g = 9.81;
real D = 0.05; /*inlet size*/
real PI=3.14159;
int time_step = N_TIME; /*returns time step number*/
real P0 = rho*g*Q0;
real A = PI*D*0.125; /*inlet area*/
real mem = F_UDMI(f,thread,0);

if(time_step = 1){newQ = Q0} /*initializing newQ*/
else{newQ = mem}

begin_f_loop(f, thread)
{
Q = newQ - (A*vel*dt);
F_PROFILE(f, thread, nv) = Q*P0/Q0;
mem = Q;
}
end_f_loop(f, thread)
}


When I try to interpret it, I get the following error messages:
Error: W:\Fluent files\Slug\2D\l1\pressure10.c: line 26: parse error.
Error: W:\Fluent files\Slug\2D\l1\pressure10.c: line 29: f_loop_last: undeclared variable

Can someone help me out with this.
Thanks,
Pranab