UDF to extract the velocity

siamak1438 · October 16, 2015, 01:22

Hello Guys,
I need to define a plane in the middle of the geometry (3D) and then extract the velocity of each node in that plane.The Id of that plane is 6, so I wrote the following UDF abut it is not working. Which part do you think is not correct?

#include "udf.h"
#include "mem.h"
#define thread_ID 6

DEFINE_ON_DEMAND(INIT)
{
Domain *domain;
Thread *t;
cell_t c;

FILE *Fileoutput;
int n,Iter;

domain = Get_Domain(1);
t = Lookup_Thread(domain, thread_ID);
Fileoutput=fopen("VEL.txt","a+");

begin_c_loop(c, t)

{
fprintf(Fileoutput,"\n %f %f %f", C_U(c,t), C_V(c,t), C_W(c,t));
}

end_c_loop(c, t)

fclose(Fileoutput);

}

`e` · October 17, 2015, 01:32

Are you receiving any compiler errors, is the text file being opened and is any text being written to this file?

Try printing the velocities to the screen (using the Message() function inside your cell loop) to help debug your problem.

pakk · October 19, 2015, 08:32

Quote:

but it is not working

Be more specific.

Do you have problems with compiling? Interpreting? Loading? Running? Getting results? Showing results?

October 16, 2015, 01:22	UDF to extract the velocity	#1
siamak1438 Member Siamak Join Date: Jul 2014 Location: Australia Posts: 36 Rep Power: 12	Hello Guys, I need to define a plane in the middle of the geometry (3D) and then extract the velocity of each node in that plane.The Id of that plane is 6, so I wrote the following UDF abut it is not working. Which part do you think is not correct? #include "udf.h" #include "mem.h" #define thread_ID 6 DEFINE_ON_DEMAND(INIT) { Domain domain; Thread t; cell_t c; FILE *Fileoutput; int n,Iter; domain = Get_Domain(1); t = Lookup_Thread(domain, thread_ID); Fileoutput=fopen("VEL.txt","a+"); begin_c_loop(c, t) { fprintf(Fileoutput,"\n %f %f %f", C_U(c,t), C_V(c,t), C_W(c,t)); } end_c_loop(c, t) fclose(Fileoutput); }

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October 17, 2015, 01:32		#2
`e` Senior Member Join Date: Mar 2015 Posts: 892 Rep Power: 18	Are you receiving any compiler errors, is the text file being opened and is any text being written to this file? Try printing the velocities to the screen (using the Message() function inside your cell loop) to help debug your problem.