[PratikChalke]

Well my Velocity at inlet and outlet are about 2m/s and 3.5m/s respectively, but I am getting relatively high velocities in the impeller region also I the velocity contours have centre at different location then the impeller. Is this because the rotation origin I have provided is wrong? Because I changed the origin of geometry in Spaceclaim before meshing, although the geometry was designed in Solidworks.

[MarcoC501]

The erroneous behaviour you see may have several causes, from modeling (mesh, solver...) to geometry and boundaries.

Without further info, I cannot help more

[NickFL]

Is this because the rotation origin I have provided is wrong?

Just looking at the results, that was my first guess. Double check that. The look in some other planes perpendicular to this one.

[PratikChalke]

I recreated the geometry and did everything over again, and now Velocity Contour seems to be normal but now I am getting issue in CFD POST where the streamlines are not complete till the end if anyone knows please help.

https://drive.google.com/file/d/1Jun...ew?usp=sharing

https://drive.google.com/file/d/1yka...ew?usp=sharing

https://drive.google.com/file/d/1OPZ...ew?usp=sharing

[MarcoC501]

I had a similar issue once, and I could not solve it in CFD-post. I had to switch to Ensight, where the streamlines are treated better.

Maybe someone can provide better help.

[NickFL]

Yes CFD Post has problems when crossing an interface, but it is much better than what is Fluent post-processing. The problem arises from a drastic change of the angle in streamlines at the interface. There are settings where you can change the integration accuracy, and it may let some through. Looking at the velocity contours, I can almost visualize the grid. This is an indication that integration along the streamlines will change per control volume, and at the interface it gives up.



Go back and double-check the interfaces. What rotating model are you using at the interface? What does the mesh look like?

[PratikChalke]

Originally Posted by NickFL

What rotating model are you using at the interface? What does the mesh look like?

I am using frozen rotor approach. I didn't exactly understood what you mean by What does my mesh looks like could your please elaborate? Thank Your for your replies

[NickFL]

The contours are not smooth. If you were to plot the mesh on the same plane as these velocity contours, I would expect the contours to follow the mesh lines. This is an indication that the mesh should be refined and that uncertainty in the integration could be the reason why the streamlines end. Are you limited to a certain number of elements (student license or something similary)? If not, maybe increase the resolution and see if that helps.

[PratikChalke]

Thank Your very much for your help, I will try what you said.