||April 3, 2010 11:44
CFX: Transient sim with fluid-fluid domain interface
I'm simulating a Kaplan hydraulic turbine. I got a good convergence in steady state, but I'm studying unsteady flows and of course is needed to carry out transient simulations.
I'm using a fifth part of runner subdomain and a complete draft tube geometry (the water conduit to the exit), this is equivalent to said a pitch angle for side one equal to 72 degrees and a pitch angle for side two equal to 360 degrees. Then I can see a very good behavior of oscillations due to blade passage frequency in the outlet of the runner but it didn't pass to the draft tube subdomain :(. So, what's happens? From the draft tube point of view it's as the fifth part of runner is a total water passage way.
Someone can give me a recommendation to try to solve it.