[burakaltintas]

Hi,

I am running steady, periodic cavitation case for the out-design parameters of a Francis runner. it has 4 million boundary layer mesh (unstructured), all y+ values on the blade are lower than 2. Max aspect ratios in layers are lower than 10000( I read that this is acceptable for boundary layer meshes).

I have two problem. Firstly, my single phase simulations,which are used as initial guess, were converged to 1e-5. However, the cavitation simulations have not converged to 1e-5. Secondly, some runs give backflow in both inlet and outlet, is it normal? if it is not normal, how can i cope with it.

Any help will make me happy!



A wall has been placed at portion(s) of an INLET |
| boundary condition (at 15.8% of the faces, 0.1% of the area) |
| to prevent fluid from flowing out of the domain. |
| The boundary condition name is: R1 Inlet. |
| The fluid name is: Water. |
| If this situation persists, consider switching |
| to an Opening type boundary condition instead. |
+--------------------------------------------------------------------+
+--------------------------------------------------------------------+
| ****** Notice ****** |
| A wall has been placed at portion(s) of an INLET |
| boundary condition (at 15.8% of the faces, 0.1% of the area) |
| to prevent fluid from flowing out of the domain. |
| The boundary condition name is: R1 Inlet. |
| The fluid name is: Vapour. |
| If this situation persists, consider switching |
| to an Opening type boundary condition instead. |
+--------------------------------------------------------------------+
+--------------------------------------------------------------------+
| ****** Notice ****** |
| A wall has been placed at portion(s) of an OUTLET |
| boundary condition (at 8.1% of the faces, 0.3% of the area) |
| to prevent fluid from flowing into the domain. |
| The boundary condition name is: R1 Outlet. |
| The fluid name is: Water. |
| If this situation persists, consider switching |
| to an Opening type boundary condition instead. |
+--------------------------------------------------------------------+
+--------------------------------------------------------------------+
| ****** Notice ****** |
| A wall has been placed at portion(s) of an OUTLET |
| boundary condition (at 8.1% of the faces, 0.3% of the area) |
| to prevent fluid from flowing into the domain. |
| The boundary condition name is: R1 Outlet. |
| The fluid name is: Vapour. |
| If this situation persists, consider switching |
| to an Opening type boundary condition instead.

[MFGT]

Are you sure you are in the right sub forum?

This here is not about Convergence, its the CONVERGE CFD software sub forum.

[burakaltintas]

Thanks, i made a mistake