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Old   February 8, 2013, 04:52
Default SU2 Residuals
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Roberto Pieri
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Hallo,

I am not able to understand how residuals are calculated.
Are they the sum of all residuals in each cell or the maximum value in the computational domain?
And also, are values saved in the history.csv the log10 of the ratio Res/Res_ref, where Res_ref is a reference value, or simply the log10 of the residuals?

Thank you,
Roberto
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Old   February 15, 2013, 20:03
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Francisco Palacios
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The residual is the L-2 norm of the residual in the entire domain, and then we compute the log10.

My recommendation is to use tecplot (it is possible to obtain an evaluation copy), the paraview output is unsupported.

Cheers,
Francisco
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Old   February 17, 2013, 12:44
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Roberto Pieri
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Thank you Francisco for the reply.

Cheers,
Roberto.
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Old   March 15, 2013, 07:19
Default SU2 residuals
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malik
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Hi,

I am running Inviscid ONERA M6 mesh using the SU2 code. I have run it but it stops after 193 iterations, iwant to increase the number of iterations to to 1500 so plz can you tell what i have to change in cfg file.

Thanks in advance

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Malik
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Old   March 15, 2013, 07:36
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Samuele Z
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Hi Malik,

this is the entry to change the max number of iterations
Code:
% Number of total iterations
EXT_ITER= 99999999999
Nevertheless, if it exits after 193 steps it is probably due to a convergence criteria.

Please, post your config file.
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Old   March 15, 2013, 16:56
Default SU2 residuals
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malik
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Hi samiam,
there is no error, i need to change convergence criteria

thanks
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Old   June 17, 2013, 07:51
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Roberto Pieri
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Hi,

I have other questions regarding residuals.

1. Where can I find the strings of the code where residuals are computed?
2. Is it possible to save residuals in the output file? I need to know at least the infinite-norm of residuals.
3. When running SU2_CFD, it prints "Maximum residual: -3.8985e+00, located at point 49659."; I think it is the maximum Res(rho) in the domain, is it right?

Cheers,
Roberto
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Old   March 31, 2016, 21:55
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Oliver V
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I'm sorry but your answer about the residuals is not clear to me. I get you use the RMS norm on the residuals, but I'm still wondering about the second question from Roberto:

Quote:
Originally Posted by robyTKD View Post

are values saved in the history.csv the log10 of the ratio Res/Res_ref, where Res_ref is a reference value, or simply the log10 of the residuals?

Roberto
in other words, are the calculated residuals relative or absolute?

(My guess is they are absolute since you only mentioned the L-2 norm... but I need to ask).

Thanks,
Oliver
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Old   April 5, 2016, 18:46
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Tansu
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Quote:
Originally Posted by robyTKD View Post
Hi,

I have other questions regarding residuals.

1. Where can I find the strings of the code where residuals are computed?
2. Is it possible to save residuals in the output file? I need to know at least the infinite-norm of residuals.
3. When running SU2_CFD, it prints "Maximum residual: -3.8985e+00, located at point 49659."; I think it is the maximum Res(rho) in the domain, is it right?

Cheers,
Roberto
Hi Roberto,

for your 3rd question, as far as i know you are right, it is res(rho).

Regards,
Tansu
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