Body force - Does it work?

Jan Rusås

In many of the applications I use CFD for, is orifice plates (plates with many holes for equalising the flow distribution) or/and also heating surfaces in the flow domain. It is not possible to include the orifice plates in detail, it would mean modelling of 10.000 holes and the heating surface are often tubes with fins or pins, which again would be impossible to include. The normal approach I use is a porous zone with body forces with an isotropic resistance, dp=K*u^2

Has anyone done a detailed study and compared how good an approximation the porous region with resistance is? How well is the flow distribution, pressure drop and also important the kinetic energy predicted downstream.

Thanks in advance Jan