[DuYikang]

Hello everyone! I am encountering an interesting problem.How to setthe negative gauge pressure to zero when negative values occur in the hydrodynamic bearings or hydrostatic bearings? From the fluent help, the define_adjust can change the pressure and velocity in every iterative step.However, it can't make it.The programm as follows：
#include "udf.h"
DEFINE_ADJUST(adjust_pressure, domain)
{
Thread *t;
cell_t c;
face_t f;
thread_loop_c(t, domain)
{
begin_c_loop(c, t)
{
if (C_P(c, t) < 0)
C_P(c, t) = 0;
}
end_c_loop(c, t)
}
thread_loop_f(t, domain)
{
begin_f_loop(c, t)
{
if (C_P(c, t) <= 0.0)
C_P(c, t) = 0.0;
}
end_f_loop(c, t)
}
}


Although the DEFINE_EXECUTE_AT_END can make it, it is unreason.The programm is from this forum.(UDF to fix the pressure in domain - not working)
#include "udf.h"
DEFINE_EXECUTE_AT_END(pressure_adjust)
{
Domain *d;
Thread *t;
cell_t c;
face_t f;
d = Get_Domain(1);
thread_loop_c(t,d)
{
begin_c_loop (c,t)
{
if (C_P(c,t)<=0.0)
C_P(c,t)=0.0;
}
end_c_loop (c,t)
}
thread_loop_f(t,d)
{
begin_f_loop(c,t)
{
if (C_P(c,t)<=0.0)
C_P(c,t)=0.0;
}
end_f_loop(c,t)
}
}

[KaLium]

Have you tried solve/controls/limits?

https://www.sharcnet.ca/Software/Flu...g/node1381.htm

[DuYikang]

Originally Posted by KaLium

Have you tried solve/controls/limits?

https://www.sharcnet.ca/Software/Flu...g/node1381.htm

Thank you for replying me.The method proposed by you had tried,but fail to success.