CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   Main CFD Forum (https://www.cfd-online.com/Forums/main/)
-   -   How to calculate swirl without using swirl generators (https://www.cfd-online.com/Forums/main/109619-how-calculate-swirl-without-using-swirl-generators.html)

 drsrinivasan November 22, 2012 00:28

How to calculate swirl without using swirl generators

Sir,
I am working on simulation of combustion process in axial flow gas tubine combustor. The main reference journal paper has s 2-D model and no information about the swirler. They have solved for swirl number 0.37,0.76 and 1.2. The air inlet ratios are as follows
primary(axial):secondary(axial):dilution(axial) as 5:7:8. Now, I am looking forward for a method to calculate swirl. Is there any formula/method to calculate swirl in terms of velocities. I request you to help me.

 Rami November 22, 2012 04:06

I believe the swirl is defined (in tensor notation) as 2Wik=Ui,k - Uk,i (where Ui is the velocity vector and "," denotes covariant derivative), i.e., the antisymmetric part of the strain rate tensor. In 2D x-y plane flow the only non-zero Wik's are Wxy = -Wyx = (Ux,y-Uy,x)/2.

 All times are GMT -4. The time now is 08:48.