conservation of angular momentum in swirling flow
conservation of angular momentum in swirling flow
(OP)
Hi, I am working with CFD to analyze a swirling burner with a square section combustor. When I calculate the angular and the axial momentum inside the combustor, it decreases the more I check downstream to the burner exit. Do you know what would create a decrease in the angular and axial momentum inside a square section combustor? Should the swirl number variate inside the combustor?
Thank you very much for your help.
Thank you very much for your help.





RE: conservation of angular momentum in swirling flow
RE: conservation of angular momentum in swirling flow
Thanks
RE: conservation of angular momentum in swirling flow
Even in a free jet, the flow will interact with the outside atmosphere eventually (unless exhausting into vacuum), and the swirl will dissipate.
That said, in cylindrical swirling flows, the core region of the flow often persists a long distance downstream; I could imagine that a square channel would cause more rapid dissipation due to the disturbances formed in the corners (additional axial vorticity that gets (robs) its energy from the core flow).
Swirl number is defined by...? I assume some average swirl velocity or momentum divided by axial velocity or momentum? Again, no, the swirl number would be preserved only in the core region, away from the wall disturbance.
RE: conservation of angular momentum in swirling flow
Thank you very much for your support.