Residual Plot Convergence Do not Converge

quasar

I am conducting a research study on a Hydro Turbine with a Venturi Effect Induced Turbine Enclosure and would desire to determine the velocity at the throat section/middle section of the model as my desired results. However, i tried setting up the CFD system in Simlab with the relative boundary conditions that I think are relevant for the study mainly inlet, outlet, and walls. The convergence plot for my residuals do not converge is my initial assumption I would like to ask for advice on where I went wrong and what I should do in order to improve my convergence for the residuals. I have attached below the necessary details for the boundary conditions, mesh controls, log file, and convergence plots. Thankyou for your help Altair community.

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James Lewis

This is my database file or my set-up file if I am correct. I cannot attach the solution file in the attachments. Thankyou for your response!

Hi quasar,

 

I checked your model and found out some points that I think it would affect your convergence:

1. your mesh quality: there are both 2D and 3D mesh are in the solution, but with cfd analysis you only need your 3D mesh. Moreover, your mesh at inlet and outlet are also bad.

2. intitial condittion of pressure: you are using gauge scale for pressure, therefore I think your initial pressure value should be 0.

 

I re-defined your model to have better convergence, you can find the model and results from attachment.

20240326-turbin not converged.7z