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Wind profile

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phtj
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Hi all,

We are trying to create a wind tunnel simulation (using the smoke solver) around a building. For this, the wind speed needs to lower at the bottom and higher at the top of the building.

Here is an image that shows the wind speed profile:
http://www.wbdg.org/images/airbarriers_3.gif [wbdg.org]

In the ‘Smoke Object’ node, we can set a constant wind speed in “Wind Tunnel Direction”. Is there a way we can vary the wind speed with height?

Thanks
Patrick
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PradeepBarua
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https://vimeo.com/44129053 [vimeo.com]

Check around 17:00 min where Scott explain how to create custom wind field.
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phtj
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Thanks Pradeep for the tip on the video. I created a test model - the file is attached.

It kind of works at the start - .e. the wind velocity at the start of the animation is slow at the bottom and fast at the top. But it does not stay that way - strange things start happening. Basically, the velocity of the wind at the top where there are no obstructions should stay more or less constant - which is not the case.

Any suggestions on how to fix this? I get the feeling the problem may be to do with the inflow and outflow of the wind at the boundary.

Attachments:
trial_wind_tunnelpj4.hipnc (650.6 KB)

Patrick
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phtj
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Here is an even simpler example with no obstructions at all. It is just some wind blowing through an empty space. What I would like to achieve is to have a constant wind flow, with the wind at the top moving faster than the wind at the bottom.

See attached file (v14).

Attachments:
trial_wind_tunnelpj5.hipnc (521.4 KB)

Patrick
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vigneshkaushik
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Does changing the border type from constant to repeat help? I have attached screenshot of both scenarios. In border type=repeat, the volume seems to wrap returning values from opposite side of the volume. I am not entirely sure if that is the same as a constant initial wind profile. Can someone clarify pls?

Attachments:
screenshot_41.png (934.1 KB)
screenshot_11.png (968.0 KB)

Cheers
ViSiKa
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old_school
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Here's my shot at it.

- velocity source using a user-placed box and ramp to define wind force in Y.
- Smoke container with velocity only. No smoke (not needed). Visualize vel field.
- building collider and ground plane collider
- volume closed boundaries open in +Z only
- Add vortex confinement to velocity.

Pretty cool.

Attachments:
bulding_wind_tunnel_0156.jpg (852.3 KB)
building_wind_tunnel_setup.hip (652.9 KB)

There's at least one school like the old school!
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