[kcgmech]

Dear Fluent user,
i am solving TIG welding simulation using fluent. i need to assign temperature dependent surface tension temperature coefficient for Marangoni convection. but there is a provision to use constant value. how can i use temperature dependent data ? kindly help me out in this boundary condition.

[Ebr amin2003]

Originally Posted by kcgmech

Dear Fluent user,
i am solving TIG welding simulation using fluent. i need to assign temperature dependent surface tension temperature coefficient for Marangoni convection. but there is a provision to use constant value. how can i use temperature dependent data ? kindly help me out in this boundary condition.

Dear Ganesh,

You need a UDF to define surface tension temperature coefficient.

/************************************************** *************
Surface Tension Coefficient UDF for the VOF Multiphase Model
************************************************** *************/

#include "udf.h"
DEFINE_PROPERTY(sfc, c, t)
{
real T = C_T(c,t);
return 1.23 - 0.004*T + 5.0e-6*T*T;
}