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Using streamlines in RBM

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Old   February 3, 2015, 13:23
Default Using streamlines in RBM
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Hi all

I am struggling on how to simulate the rotation in my solutions with streamlines.

As you can see in the attached image I clearly have rotation from my HAWT, this was done via volume render after an unsteady reynolds stress RBM simulation. However, once I try to visualize the rotation with streamlines.

I imagine its something simple due to using a rotating and stationary region in RBM, but all I get is straight lines back to the end of my wind tunnel from whatever parts I use to seed my streamlines

Any input appreciated,
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Old   February 10, 2015, 14:21
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No body come across this problem before?
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Old   February 10, 2015, 19:33
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Make some cuts with vectors and see if they show your rotation. That'll say if the streamlines are the problem or not.

It looks like they transition to straight really fast, what does the grid look like?
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Old   February 11, 2015, 08:59
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Quote:
Originally Posted by me3840 View Post
Make some cuts with vectors and see if they show your rotation. That'll say if the streamlines are the problem or not.

It looks like they transition to straight really fast, what does the grid look like?
Yeah all ok on vector plots and any scalar scene I produce, volume renders also pick it up. By grid do you mean mesh?
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File Type: jpg RST_TSR5.09_1deg_Unsteady_Final Solution_Mesh Scene 1.jpg (76.2 KB, 18 views)
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Old   February 11, 2015, 22:06
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Few things:

The growth rate on the exterior is tremendous
Your domain is probably not large enough
Lower the volume control blend factor to reduce the near-wall effect of the volume control
Why do you have prisms on the top of the domain?

And another thought: The volume render images can go beyond your grid resolution. Why don't you try and produce the same images with isosurfaces. What does that look like?
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Old   February 12, 2015, 05:12
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Quote:
Originally Posted by me3840 View Post
Few things:

The growth rate on the exterior is tremendous
Your domain is probably not large enough
Lower the volume control blend factor to reduce the near-wall effect of the volume control
Why do you have prisms on the top of the domain?

And another thought: The volume render images can go beyond your grid resolution. Why don't you try and produce the same images with isosurfaces. What does that look like?
Hi me3840,

The prism layers on the top because the simulation is replicating a wind tunnel experiment. The cell growth rate is as so, because I wanted as much detail in the wake region as possible. Mesh sensitivity study was complete, and given the results, a slower growth rate outside the wake region had no great bearing on the results.

On the results, on the post processing done thus far, the solution appears to correlate very well with exp. results so I'm happy with the mesh for both the K-Omega and Reynolds Stress solutions.

What do you mean by the volume renders going beyond my grid resolution?

Iso-Surface's also work very well.

Any idea about the stream lines?

Cheers
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