viscosity.c

fluent培训教程中的udf例子和说明

/**************************************************************/
/*                                                            */
/* User-Defined Functions for temperature-dependent viscosity */
/* FLUENT 5.0                                                 */
/*                                                            */
/* Author: Liz Marshall                                       */
/*   Date: February 1998                                      */
/*                                                            */
/**************************************************************/



#include "udf.h"


DEFINE_PROPERTY(user_vis, cell, thread)

{

  float temp, mu_lam;

  temp = C_T(cell, thread);

  {

/* If the temperature is high, use a small, constant viscosity */

  if (temp > 288.)
      mu_lam = 5.5e-3;

/* Otherwise, use a profile to get higher viscosity values */

  else if (temp >= 286. && temp <= 288.)
      mu_lam = 143.2135 - 0.49725 * temp;

  else
      mu_lam = 1.0;
}
  return mu_lam;
}