[sherifkadry]

Hello,
I was hoping any CFX turbo gurus could give me some guidance on achieving a converged model of a axial turbine. The model uses a straight stator and bowed rotor blades. I have actual experimental data to use for my boundary conditions. The rotor stage mesh was obtained from a colleague and had performed fairly well in a previous model (previous models had bowed stator and rotor blades). I needed to create a straight stator blade mesh which I did using ICEMCFD.
Model specifics:
-2-stage model (stator and rotor geometry are the same for each stage)
-steady state model
-stage interface was used the pitch to pitch ratio is 1.0 equal blade numbers for stator and rotor.
-total pressure inlet bc specified (based on experimental data).
-exit static pressure bc specified (based on experimental data).
-SST model was used as recommended by ANSYS

The main problem is the model does not converge, I have investigated the stator mesh and it seems to be okay (refining or coarsening of the mesh seems to still produce a diverging model) that could also be a problem point not really sure as I am mainly an experimentalist. Could this be an issue with the stage interface definition and aligning the stator exit and rotor inlet? Any tips or advice would be much appreciated

Sherif

[ckleanth]

not a turbo expert but check the faq for convergence problems

my guess (if you checked everything else is fine) is that your problem is not steady state

[ghorrocks]

Here's the link George referred to: http://www.cfd-online.com/Wiki/Ansys...gence_criteria