CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   OpenFOAM Post-Processing (https://www.cfd-online.com/Forums/openfoam-post-processing/)
-   -   Streamlines does not make sense. (https://www.cfd-online.com/Forums/openfoam-post-processing/217361-streamlines-does-not-make-sense.html)

innvah May 9, 2019 09:01

Streamlines does not make sense.
 
1 Attachment(s)
Hi,

I am working on a project regarding a rotating propeller with OpenFOAM 6.
I am using pimpleFoam as solver and AMI. (The size of a compressed case was too large to upload.)
As far as I understand the case runs fine (even with coarse mesh), but during the post-processing I do not quite understand the streamlines or the output torque.

I recently noticed a beginner mistake regarding the rotation. As the case is set-up the propeller is to rotate clockwise. By defining a negative omega in dynamicMeshDict this is enabled.

The output torque is unexpectedly low and while studying the stream lines in paraView 5.6 I can see that the flow is not going through the turbine, but simply flows into the blades and then stops.

In the early phases of this project I had a positive omega. This is not (as far as I understand) the correct way of rotation. Nevertheless, the torque output values are more reasonable and the flow moves through the propeller, not directly into the blade surface wall.

Does anyone have some helpful tips on what can be wrong?
Thank you in advance. Let me know I can assist you in understand the problem further.

Best regards,
innvah


All times are GMT -4. The time now is 19:00.