how to write an UDF programming in 3D

coolyihao · March 16, 2009, 08:15

i have a 3D domain as a seawater and a turbine locate inside the seawater.. I had set the inlet as velocity inlet in Gambit..And now come into Fluent, i have to use a UDF programming to set a parabolic flow veloctiy inlet and difference pressure at the inlet.. cuz when the increasing the depth(h) , pressure will increse as well.. But i dont know how to write a programme about this 3D domain... Anyone can help? thanks

milton.tafadzwa · March 16, 2009, 08:59

You can try this maybe it will work.
#include "udf.h"
Define all your constants here.
DEFINE_PROFILE(inlet_velocity, thread, index)
{
real x[ND_ND];
real y, z;
face_t f;
begin_f_loop(f, thread)
{
F_CENTROID(x,f,thread);
y =? ; write value of z and y at your entrance.
z=?;
F_PROFILE(f, thread, index) = write your parabolic equation here;
}
end_f_loop(f, thread)
}

March 16, 2009, 08:15	how to write an UDF programming in 3D	#1
coolyihao New Member oscar Join Date: Mar 2009 Posts: 7 Rep Power: 17	i have a 3D domain as a seawater and a turbine locate inside the seawater.. I had set the inlet as velocity inlet in Gambit..And now come into Fluent, i have to use a UDF programming to set a parabolic flow veloctiy inlet and difference pressure at the inlet.. cuz when the increasing the depth(h) , pressure will increse as well.. But i dont know how to write a programme about this 3D domain... Anyone can help? thanks

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March 16, 2009, 08:59		#2
milton.tafadzwa New Member Mavis Milton Join Date: Mar 2009 Posts: 10 Rep Power: 17	You can try this maybe it will work. #include "udf.h" Define all your constants here. DEFINE_PROFILE(inlet_velocity, thread, index) { real x[ND_ND]; real y, z; face_t f; begin_f_loop(f, thread) { F_CENTROID(x,f,thread); y =? ; write value of z and y at your entrance. z=?; F_PROFILE(f, thread, index) = write your parabolic equation here; } end_f_loop(f, thread) }