Learning Forum

[sidkamat]

Hi. I am trying to add an additional force on the tracked particle in the DPM. I am getting the error "TP_POS: undeclared variable" for the following UDF:

/*UDF for calculating DEP force*/

#include "udf.h"

#include "dpm.h"

#include "dpm_types.h"

#define pi 3.141592

/*Define parameters*/

#define km 1.0

#define epsilon 8.85e-12

#define D 1.0e-6

#define L 10.0e-6

#define alpha 1130

#define V 7000

#define R2 1.111/100

#define R1 0.794/100

DEFINE_DPM_BODY_FORCE(DEP,tp,i)

{

real beta=L/D;

real xi=beta/sqrt((beta*beta-1));

real c1=atan(xi);

real f=xi*((1-xi*xi)/c1+xi);

real Fd=0;

if(TP_POS(tp)[0]>=0.366)

{

Fd= (-1*pi*km*epsilon*D*D*L/6)/(alpha/(alpha-1)-f)*(V/log(R2/1))*(V/log(R2/1))*1/TP_POS(tp)[1];

}

else

Fd=0;

return(Fd/P_MASS(tp));

}

Can anyone identify what is wrong?

[DrAmine]

Which release version are you using?

[sidkamat]

I'm using 21.1.0

[DrAmine]

Weird. Csn you try a simpler UDF without the define section ( the pre-processor type). Also remove the empty line below the macro. Please report back