CAPE Forum

Ansys => Fluent => Topic started by: pico on February 12, 2012, 12:24:19 PM

Title: How to calculate heat transfer rate within UDF?
Post by: pico on February 12, 2012, 12:24:19 PM
Hi,

Within a FLUENT UDF, how can I calculate the total heat transfer rate (radiative + convective), radiation heat transfer rate, or the absorbed radiation flux on surfaces?

Title: Re: How to calculate heat transfer rate within UDF?
Post by: william on February 12, 2012, 12:26:21 PM
Use the following macros

1. BOUNDARY_HEAT_FLUX(f,tf) to obtain the total heat transfer rate
2. BOUNDARY_RAD_HEAT_FLUX(f,tf) to obtain the radiation heat transfer rate
3. F_DO_QA(f,t,nb) to obtain the absorbed radiation flux when using the DO model

Note that "FLUX" in the macro is a mis-nomer and it gives the total heat transfer rates in watts and NOT the heat flux in watts/m2.

C_ABS_COEFF(c,t) gives you the absorption coefficcient at a cell. This is not the same as the absorbed radiaiton flux at the wall.