Gamma Uniformity Index

The Gamma Uniformity Index is a measure of flow uniformity on a clip plane.

It is the normalized RMS of the difference between the local velocity and the spatial mean of the velocity integrated over the area of the clip plane.  See the attached equation.

Gamma Uniformity Equation

Equation for Gamma Uniformity

Attached is a demonstration of EnSight Python for calculating the Gamma Uniformity Index. This is only intended as a prototype demonstration script for calculating this variable.

Directions for use: make a clip plane in your flow. Select the clip plane part.  If your velocity variable is different than ‘VELOCITY’ then you will have to edit this .py file to the correct variable name. Now run this script. You will have several intermediate variables calculated, but the gamma uniformity index is a constant named gam_uniform.


Leave a Reply