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Old   August 28, 2009, 04:30
Default Convergent divergent nozzle
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mistry
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Dear sir,

I am doind analysis of CD nozzle. with simple example with variation of pressures to study flow behaviour inside. also want to capture shock in it.. i took pressure 1 bar at inlet ,0.54 at outlet(critical pressure ratio). i am not getting convergence and after some convergence i am getting mass flow rate parameter along the center portion of geometry...

Weather my BC are wrong or my understading is wrong please guide me.

The CCL file,Mesh,convergence plot i am attaching here
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File Type: jpg convnozzle.jpg (39.9 KB, 37 views)
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File Type: txt CCL.txt (6.1 KB, 22 views)
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Old   August 28, 2009, 05:26
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well maybe the simulation is transient?

have you read the faq and especialy the section for convergence?
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Old   August 28, 2009, 06:27
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no man please refer CCL>TXT ... analysis is steadystate
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Old   August 28, 2009, 06:48
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i know you setup the simulation as a steady state.. but is it?
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Old   August 28, 2009, 07:33
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It may be transient but there are a lot of other things to check first. This question has been asked millions of times so here's my best guide as to how to proceed.
http://www.cfd-online.com/Wiki/Ansys...gence_criteria
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Old   August 29, 2009, 12:06
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How do you know that's not a converged solution given your conditions?
What are your criteria?
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Old   September 16, 2009, 02:40
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Hi Mistry,

I think you will not get better convegence than you have achieved. It may be becuase you problem can be bestly described by LES.

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