Help! -User Difined Functions----Drag Coefficient

Colin

Hi,

I am using Eulerian Model for multiphase flow. In the model, the drag coefficient is 1.0. And I defined the UDF of Drag coefficient as follows:

#include "udf.h"

DEFINE_EXCHANGE_PROPERTY(drag, cell, x_thread, s, f) { Cd = 1.0; return Cd; }

When the UDF is interpreted, Fluent says "Cd" is an undeclared variable. Even if I declare Cd is a real later, Fluent still showed me the same message.

Could someone help me?

Thank you.