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April 25, 2013, 08:03 |
characteristic boundary conditions
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#1 |
New Member
Join Date: Apr 2013
Posts: 15
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Hi all,
I would like to make sure if I get the idea right about the characteristic boundary conditions. Say, in the case of the inflow being subsonic and the outflow being supersonic, how many boundary conditions I have to impose? The flow is 3D. I guess the answer is that since the goal is to zero the inflow characteristics, I have to impose two boundary conditions at the inlet (for u+a and u characteristics) and do nothing for the outlet. Is this correct? What if in this case, I set all the inflow to zero? Will this generate any spurious waves? Best, Shu |
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April 25, 2013, 10:14 |
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#2 | |
Senior Member
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 6,768
Rep Power: 71 |
Quote:
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April 26, 2013, 11:01 |
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#3 | |
New Member
Join Date: Apr 2013
Posts: 15
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Quote:
To zero the characteristics means we don't want any reflection occurring at the boundary, so the boundary condition will mimic an infinite boundary condition. Shu |
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April 26, 2013, 11:30 |
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#4 | |
Senior Member
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 6,768
Rep Power: 71 |
Quote:
ok, however as I know the correctness of the bc.s setting for subsonic/supersonic flows is not sufficient to avoid reflection but it depends on further issues. As an example, this old paper illustrated some cases http://www.sciencedirect.com/science...21999192900462. Of course, many other recent papers were published |
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