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Directional loss model - describing a porous plate |
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July 20, 2012, 15:35 |
Directional loss model - describing a porous plate
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#1 |
Senior Member
Erik
Join Date: Feb 2011
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Greetings,
I am modeling a liquid domain which has a perforated plate. I know the streamwise directional loss coefficient but am having trouble estimating a realistic transverse loss coefficient. right now I'm just using 1/10 the streamwise coefficient, but am trying to see if I cane comehow describe it better. Has anyone seen any good resources/papers to calculate the transverse loss coefficient, or have any experience? I found one: "Compact CFD Modeling of EMC Screen for Radio Base Stations: A Porous Media Approach and a Correlation for the Directional Loss Coefficients", but it is for air and the study is very different than my flow characteristics. Thanks in advance |
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July 20, 2012, 18:04 |
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#2 |
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Glenn Horrocks
Join Date: Mar 2009
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A perforated plate sounds thin. In that case there would be little thickness for the transverse flow to do anything. This means the transverse coefficient will not matter much.
I recommend you do a sensitivity analysis of it, and I suspect you will find that it will not make much difference, so you can enter anything within a wide range of the streamwise loss coefficient. |
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July 21, 2012, 12:06 |
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#3 |
Senior Member
Erik
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Thanks for the reply,
That was my thinking that it shouldn't have much effect on the transverse flow. I'll do the sensitivity study with 0%, 10% and 20% the flow restriction of the streamline direction. |
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August 5, 2013, 09:45 |
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#4 |
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Koen Stegeman
Join Date: Jan 2010
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Did you have any result? I agree with flows coming with no angle of attack, but what about flows coming in with an angle of attack. Then it makes a difference when choosing directional loss.
My question is what should be this factor for 45º flows? |
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August 5, 2013, 11:11 |
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#5 | ||
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OJ
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Quote:
If it is more than 0.015, it is regarded as thick plate. And generally the transverse loss coefficient will be far larger than streamwise coefficient for thicker plates. I don't understand why you say that you will use 1/10th of the streamwise... Quote:
OJ |
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