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Ansys Learning Forum Forums Discuss Simulation Fluids Using udf as breakage kernel Reply To: Using udf as breakage kernel

hmortaza
Subscriber
Thank you very much Kremella for your answer.
No. It happens when I start calculation.
This is the UDF exactly the same as the one in ANSYS help. The UDF is as below. I have realized that the problem is with the functions ( C_D(cell, tm) ,C_VOF(cell, thread), and C_R(cell, thread)) as I have tried constant values instead of them and it worked. Do you have any idea why this happens?
#include "udf.h"
#include "sg_pb.h"
#include "sg_mphase.h"

DEFINE_PB_BREAK_UP_RATE_FREQ(break_up_freq_tav, cell, thread, d_1)
{
real epsi, alpha, f1, f2, rho_d;
real C1 = 0.00481, C2 = 0.08, sigma = 0.07;
Thread *tm = THREAD_SUPER_THREAD(thread);/*passed thread is phase*/
epsi = C_D(cell, tm);
alpha = C_VOF(cell, thread);
rho_d = C_R(cell, thread);
f1 = pow(epsi, 1. / 3.) / ((1. + epsi)*pow(d_1, 2. / 3.));
f2 = -(C2*sigma*(1. + alpha)*(1. + alpha)) / (rho_d*pow(epsi, 2. / 3.)*pow(d_1, 5. / 3.));
return C1 * f1*exp(f2);
}
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