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i try to write a udf that detemenie the bondury condithions and u and v (x y vilocities)
how can i do it?
i wrote the folloing file:

Code:

/**********************************************************************

unsteady.c 

UDF for specifying a transient velocity profile boundary condition 

***********************************************************************/

#include"udf.h" 

DEFINE_PROFILE(unsteady_velocity, thread, position) { real x[ND_ND]; /* this will hold the position vector */ real y; face_t f; begin_f_loop(f, thread) { F_CENTROID(x,f,thread); y = x[1]; F_PROFILE(f, thread, position) = -0.06*y*y+0.06*y; F_PROFILE1(f, thread, position)=-1; } end_f_loop(f, thread)}

and it written to me: F_PROFILE1: undeclared variable
where i need to declared this variable?
thanks for the help
hilla

when i try to write it that way:

Code:

　

/**********************************************************************

unsteady.c 

UDF for specifying a transient velocity profile boundary condition 

***********************************************************************/

#include"udf.h" 

DEFINE_PROFILE(unsteady_velocity, thread, position) { real x[ND_ND]; /* this will hold the position vector */ real y; face_t f; begin_f_loop(f, thread) { F_CENTROID(x,f,thread); y = x[1]; F_PROFILE(f, thread, position) = -0.06*y*y+0.06*y; } end_f_loop(f, thread)}

DEFINE_PROFILE_y(unsteady_velocity_y, thread, position) { real x[ND_ND]; /* this will hold the position vector */ real y; face_t f; begin_f_loop(f, thread) { F_CENTROID(x,f,thread); y = x[1]; F_PROFILE_y(f, thread, position) = -1; } end_f_loop(f, thread)}

it's write to me "syntax error"

DEFINE_PROFILE and F_PROFILE are predefined macros, you cannot change as you wish. If you need a new profile change the first argument of DEFINE_PROFILE and hook it appropriately.