Total Energy and a Stage Interface

aerost · November 16, 2011, 12:22

Hello,

I am trying to solve a rotor stator problem using the total energy heat transfer model (incl. viscous work). I have a GGI stage interface between the single peridodic rotor and the single periodic stator (pitch ratio 5:7). When I converge this solution though I find that there are very large but highly localized temperature gradients in the flow right at the stage interface. The rest of the domain is pretty close to isothermal, but there are 200+ degree F gradients at the interface. Total pressure is very constant and smooth over this area though.

Looking at the monitors, all of the mass and momentum residuals converge very well, but the Energy residual seems to flat line at ~2e-3...

Would adding a pressure profile decay help this at all? Is there any way to add a "Temperature profile decay" of some sort? I think it might help the solution converge. Any other ideas?

Thnanks.

ghorrocks · November 16, 2011, 18:51

Do not activate the viscous work model unless it will significantly contribute to the result. No point in activating unnecessary models.

This FAQ should give you some tips for getting it to converge:
http://www.cfd-online.com/Wiki/Ansys...gence_criteria

November 16, 2011, 12:22	Total Energy and a Stage Interface	#1
aerost New Member Join Date: Jul 2010 Posts: 7 Rep Power: 15	Hello, I am trying to solve a rotor stator problem using the total energy heat transfer model (incl. viscous work). I have a GGI stage interface between the single peridodic rotor and the single periodic stator (pitch ratio 5:7). When I converge this solution though I find that there are very large but highly localized temperature gradients in the flow right at the stage interface. The rest of the domain is pretty close to isothermal, but there are 200+ degree F gradients at the interface. Total pressure is very constant and smooth over this area though. Looking at the monitors, all of the mass and momentum residuals converge very well, but the Energy residual seems to flat line at ~2e-3... Would adding a pressure profile decay help this at all? Is there any way to add a "Temperature profile decay" of some sort? I think it might help the solution converge. Any other ideas? Thnanks.

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November 16, 2011, 18:51		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	Do not activate the viscous work model unless it will significantly contribute to the result. No point in activating unnecessary models. This FAQ should give you some tips for getting it to converge: http://www.cfd-online.com/Wiki/Ansys...gence_criteria