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Initialisation of UDS at t=0

Dear All,

I want to calculate the concentration contour, in the three fluid zone in a transient situation. For that I need to initialize concentration equal to 1 at zone 1 at t=0 whereas for zone 2,3 concentration is equal to 0 at t=0. I am using only 1 single UDS equation. How to implement this initial condition. Any help is highly appreciated.

Find the fluid id's of the different zones, and then do something like this: copy,paste,build,load and set function hook.

Code:

#define ID_FLUID_1 136

#define ID_FLUID_2 242

#define ID_FLUID_3 281



DEFINE_INIT(Set_start_conc,d){ 

cell_t c;

Thread *t;

double x[ND_ND];

    

t=Lookup_Thread(d,ID_FLUID_1); 

begin_c_loop(c,t){

  C_UDSI(c,t,0) = 1.0 // value of user defined scalar 0     

}

end_c_loop(c,t)

        



t=Lookup_Thread(d,ID_FLUID_2); 

begin_c_loop(c,t){

  C_UDSI(c,t,0) = 0.0;            

}

end_c_loop(c,t)



t=Lookup_Thread(d,ID_FLUID_3); 

begin_c_loop(c,t){

  C_UDSI(c,t,0) = 0.0;            

}

end_c_loop(c,t)

}