Tuesday, February 10, 2009

Enable the Vorticity Magnitude Computation in Fluent Inviscid Simulations

For inviscid models, Fluent does not allow you to compute the vorticity magnitude. While it should usually be available under the velocity section of the variables to plot, an inviscid fluent model lacks this feature. I am not sure why this is the case as inviscid flows are generally rotational! Only irrotational flows have zero vorticity.

So any way, some of my models are run under inviscid flow conditions and to compute the vorticity, one may define a UDF to compute it or simply export the velocity field data and compute it in a data analysis software. I find this rather cumbersome as it cost me a lot of time and the accuracy of my computations may suffer a bit. It could have been just easier if Fluent does that automatically.

Here’s a neat trick: to enable the computation of vorticity in an inviscid Fluent model, simply change your model to laminar and you’ll see that nice vorticity magnitude variable show up!

Go to: Define/Models/Viscous and select Laminar

Voila!

Of course, you should do this after you’re done with your inviscid simulation.


Cite as:
Saad, T. "Enable the Vorticity Magnitude Computation in Fluent Inviscid Simulations". Weblog entry from Please Make A Note. http://pleasemakeanote.blogspot.com/2009/02/enable-vorticity-magnitude-computation.html

1 comment:

  1. But how could you get results in cylindrical coordinates, eg tangential velocity in a rotating flow in a cylinder.

    Wan Zaidi
    wanzaidi@yahoo.com

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