DIV(V)-QTL too large! error

[ME19B1026 SHIVA]

Hi all I am woking on a plane couette system with coriolis forcing term. At rotation rate 10 rad/sec i am getting a error of WARNING: DIV(V)-QTL too large! whereas at 0.008 rad/sec i am not getting this error. for rotation rate 10 rad/sec if I work with 1e-11 time steps it works but when I work with 1e-8 or something this error again comes. Can someone suggest me what are the possible reasons for this error because my mesh is refined nearest wall is 4e-6 and time steps and courant number is also very less in the case of 10 rad/sec

[YuHsiang Lan]

Hi,

What are the tolerances you have for the linear solvers?

The default tol are designed for the nondimensional velocity.

However, when you add rotation into forcing term, it might not maintain the same scale.

This has to do with your settings: BC and frame of reference, etc.

I'd suggest increasing the rotation rate gradually while monitoring the DIV error.

Then, reduce tol for both velocity and pressure to see whether it drops.

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Hope this helps,

Yu-Hsiang

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