[gemxx]

I want to ask a question about Residuals.

I study on the noise around a circular cylinder but the residual values of turbulence kinetic energy is not converge. I use k-omega turbulence model.
What is the reason of this ? Could you please help me about this matter ?

I upload the picture of the residuals and mesh structure in attachment. (It belongs to steady state simulation.)

[MRI]

The Tke does converge but with high residuals. Please switch off the "Normalization Option" under the monitor node for all residuals and then have a look on the residuals.

[gemxx]

Originally Posted by MRI

The Tke does converge but with high residuals. Please switch off the "Normalization Option" under the monitor node for all residuals and then have a look on the residuals.

Thank you very much for your reply. I switched off the "normalization option" under the monitor node for all residuals and then the Tke residuals decreased.But now the standard deviation of residual energy (sdr) is too high.

I added in attachment the picture of residuals at the final state.

what is the significance of "normalization option" in monitor properties? Do you think that all residuals are converge ? Can I see the residuals are converge or not by using another way ?

[gemxx]

I also added the maximum Tke value and the sum of Tke on the circular cylinder.

[MRI]

As a next step I would have a look at the wall y+ values on the cylinder surface. Try to lower them below one (by decreasing the wall distance of the first cell next to the wall) and switch on a low-y+ wall treatment in the physical models and start calculating again. To calculate the wall distance you can use this tool https://www.cfd-online.com/Tools/yplus.php