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February 6, 2017, 02:28 |
to determine Integral length scale in Fluent
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#1 |
Senior Member
raunak jung pandey
Join Date: Jun 2016
Posts: 102
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Hello everyone
I am trying to calculate integral length scale in Fluent for a fluidic oscillator. My objective is to carry out LES simulation. I am using the expression : integral length scale l0 = k^1.5 /e where k - turbulent kinetic energy and e is eddy dissipation. During post processing maximum and minimum values of turbulent kinetic energy and eddy dissipation rate is given. Can these values used to determine integral length scale. If not what is the process to determine integral length scale? Thank You Last edited by raunakjung; February 6, 2017 at 04:43. |
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February 6, 2017, 03:56 |
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#2 |
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Cees Haringa
Join Date: May 2013
Location: Delft
Posts: 607
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You can make a custom field fuction (under define) with the required equation. This will calculate the length scale in every grid cell. You can then plot it as a contour plot, export it, like you could do with any field. You can also define an equation in CFD post alternatively.
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February 6, 2017, 04:46 |
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#3 | |
Senior Member
raunak jung pandey
Join Date: Jun 2016
Posts: 102
Rep Power: 10 |
Quote:
Thank YOU |
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February 7, 2017, 10:03 |
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#4 |
Senior Member
Cees Haringa
Join Date: May 2013
Location: Delft
Posts: 607
Rep Power: 0 |
For LES, calculate the Kolmogorov scale, and try to locally refine your mesh to approx. 5-10x the Kolmgorov scale in the bulk. The finer, the more scales you resolve of course.
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eddy dissipation rate, integral length scale, turbulent kinetic energy |
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