Gauge pressure started diverging

Using SimScale Fluid Flow / CFD
1

Hi there,

I’m working on a CFD simulation of a centrifugal water pump and I keep getting this error message on my simulation runs that are failing: Gauge pressure field started diverging. Please check the mesh quality near the reported location and try refining the mesh. If the problem occurred near a boundary, please check the boundary conditions.

I’ve tried solving the problem multiple times by looking at other examples in the forum but keep getting the same error, is there anything that I am blatantly doing wrong that is making this happen every time?

Any help much appreciated.

Charlie.

2

Hey CCJ1999

Thanks for posting on the Forum, could you share the link to your project?

Best,
Satvik

4

Hi Shenoy,
thanks for the quick response, I believe I have shared the project with you, is there anything else i need to do?

Charlie

5

I am taking a look at the project now, Charlie. I will get back to you once I have a potential solution.

6

Hi @CCJ1999,

I think there a few things worth pointing out about your project:

  • The first one has to do with where the simulation diverged:

image
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If you inspect that region in the post processor on the failed runs, you’ll see a tiny gap between this blade and the face of the cylinder:

image
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Which will make the elements very distorted and probably cause divergence

For further information please check:

  • The second one has to do with the boundary conditions:

image
image1920×945 112 KB

It seems you’ve defined 0 Gauge Pressure for both the inlet and the outlet, which will make it so there is no flow on the turbine. Have you had a chance to take a look at this tutorial:

Best,
Igor