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Old   July 6, 2010, 06:30
Default heat transfer convergence
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Hi,
I am performing RANS simulation on jet impingement (full 3D model) with SST tur. model. I am wondering why the heat transfer convergence is so bad, while the momentum and turbulence are good.
Thx, Martin
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Old   July 6, 2010, 06:31
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what are the y plus values ?
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Old   July 6, 2010, 07:00
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Quote:
Originally Posted by ckleanth View Post
what are the y plus values ?
y+ < 1, actually I was running similar simulation before, only for a 5 degree cut out. there the RMS convergence was comparable. in this case the momentum and turbulence RMS is <10^-5 after 500 iterations, while the heat tr. RMS ~ 5x10^-4 (1000 it.).
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Old   July 6, 2010, 18:42
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Errors in heat transfer are typically 20-40% in turbulence modelling, especially when looking at local heat transfer rates (rather than global heat transfer). It is much harder to get heat transfer right compared to momentum. This is explained in any turbulence modelling textbook.
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Old   July 7, 2010, 02:30
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thanks for reply.
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