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November 9, 2011, 05:46 |
roughness in shallowWaterFoam
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#1 |
New Member
Wolfgang Schanderl
Join Date: Nov 2011
Location: Munich
Posts: 2
Rep Power: 0 |
Hallo everybody,
I want to do an open-channel simulation with shallowWaterFoam. How can I define the bed-roughness? Or do I have to model it somehow? Regards, Wolfgang |
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July 16, 2013, 22:51 |
Are you looking to model a free-surface flow?
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#2 |
New Member
David Jessop
Join Date: Jul 2013
Posts: 5
Rep Power: 13 |
Hi,
This reply may come far too late for the original post but I hope it may help other openfoam users. I've been trying to model certain classes of free-surface gravity currents for which the horizontal length scale (x and/or y) is much larger than the vertical scale (z). In this framework, vertical accelerations are small compared to gravity, and the conservation equations can be depth averaged which leads to what are often called the shallow water equations. For this reason, I started to investigate the shallowWaterFoam solver. However, as is described in HTML Code:
http://www.tfd.chalmers.se/~hani/kurser/OS_CFD_2010/johanPilqvist/johanPilqvistReport.pdf |
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July 22, 2013, 15:10 |
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#3 |
Member
Haomin Yuan
Join Date: Jan 2012
Location: Madison, Wisconsin, USA
Posts: 59
Rep Power: 14 |
I think you can just use a rough wall function. You may look it up in turbulence model wall function source file.
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July 22, 2013, 15:31 |
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#4 |
New Member
David Jessop
Join Date: Jul 2013
Posts: 5
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That would mean that the "rough wall" would be one of the "frontAndBack faces". I don't think that would work as the domain is only one-cell thick in the depthwise direction, but I could be wrong.
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September 2, 2013, 04:58 |
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#5 |
Senior Member
Join Date: Jul 2011
Posts: 120
Rep Power: 15 |
you are right. it would not work since it is only one cell thick. In depth averaged models the wind and bed stresses act as souce and sink to the momentum equations. I am currently working on this.
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September 4, 2013, 10:03 |
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#6 |
Member
Andreas Ruopp
Join Date: Aug 2009
Location: Stuttgart / Germany
Posts: 31
Rep Power: 17 |
hi,
for bottom roughness you just have to impose an additional source. I did that already and that works brilliantly. It is easy: Code:
...=lambda*hU andy |
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September 24, 2013, 03:49 |
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#7 |
Senior Member
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September 24, 2013, 05:33 |
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#8 |
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Andreas Ruopp
Join Date: Aug 2009
Location: Stuttgart / Germany
Posts: 31
Rep Power: 17 |
According to Jasak PhD http://powerlab.fsb.hr/ped/kturbo/Op...jeJasakPhD.pdf
I added it to momentum predictor as well as in piso-loop. |
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September 24, 2013, 06:09 |
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#9 | |
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Quote:
Last edited by haze_1986; October 3, 2013 at 05:42. |
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October 1, 2013, 02:34 |
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#10 |
Senior Member
Join Date: Jul 2011
Posts: 120
Rep Power: 15 |
Fixed, thanks
Last edited by haze_1986; October 3, 2013 at 05:43. |
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August 28, 2023, 06:23 |
the roughness
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#11 |
New Member
Join Date: Aug 2023
Posts: 8
Rep Power: 3 |
Hi everyone,
I am trying to simulate a river with openfoam, using the shallowWaterFoam solver. Is the solver still not considering bottom roughness? How may I add the manning roughness number in the simulation then? Thanks a lot in advance. |
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Tags |
open channel flow, roughness, shallow water |
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