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drsrinivasan November 22, 2012 00:28

How to calculate swirl without using swirl generators
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.

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