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3D turbulent model in pond in a very large pond- issues solving
Posted 10 ott 2011, 01:48 GMT-4 Fluid & Heat, Computational Fluid Dynamics (CFD) Version 4.1 1 Reply
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Hello,
I am trying to model the terbulent flow through a settling pond. Because the geometry is large, I am having issues solving the model. Attached is the model and I would be very thankful for any suggestions. I have a feeling that the issue is mainly with my initial conditions but I am not sure how to fix this.
I am trying to model the terbulent flow through a settling pond. Because the geometry is large, I am having issues solving the model. Attached is the model and I would be very thankful for any suggestions. I have a feeling that the issue is mainly with my initial conditions but I am not sure how to fix this.
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1 Reply Last Post 12 ott 2011, 10:55 GMT-4
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Posted:
1 decade ago
Hello,
I just realized I was not being descriptive in my question earlier.
The model is a turbulent flow in a rather large pond. It has two inlets and a single outlet. The mesh is a sweeping mesh in the area with uniform area (in the direction of flow) and free unstructured meshing in the remaining geometry.
about my errors:
1) with the 3D I get "very illconditioned pre-conditioner" in the stationary study and "failed to find consistent initial conditions" with the time dependant
2) I tried a simple 2D turbulent flow with the large geometry and it also ends up with errors. "failed to find consistent initial conditions" with the time dependant. Intrestingly, this one solves in the stationary study, but only if th emesh is coarse! With a fine mesh, it gives an error again- NaN_or_Inf_found_when_solving_linear_system_using_PARDISO
I am not sure what I am doing wrong and would be very very grateful for any help!
Thanks,
Preethi
I just realized I was not being descriptive in my question earlier.
The model is a turbulent flow in a rather large pond. It has two inlets and a single outlet. The mesh is a sweeping mesh in the area with uniform area (in the direction of flow) and free unstructured meshing in the remaining geometry.
about my errors:
1) with the 3D I get "very illconditioned pre-conditioner" in the stationary study and "failed to find consistent initial conditions" with the time dependant
2) I tried a simple 2D turbulent flow with the large geometry and it also ends up with errors. "failed to find consistent initial conditions" with the time dependant. Intrestingly, this one solves in the stationary study, but only if th emesh is coarse! With a fine mesh, it gives an error again- NaN_or_Inf_found_when_solving_linear_system_using_PARDISO
I am not sure what I am doing wrong and would be very very grateful for any help!
Thanks,
Preethi