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The power transmission is bigger than 1???

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I use the Acoustic module and calculate the power transmission properties in periodic strucutres. In some simulations, I found the power transmission is bigger than 1. I'm so cofused about it. The setting is follow:

frequency domain:

a rectuanger strucutre
the periodic condition is applied upon the left and right boundaries. the plane radiation boundary is applied upon the up and down boundries. the incidence wave with pressure p0 is applied on the up boundary.
I calculate the power transmission like this: w_in=intop1(p0^2/(2*acpr.rho*acpr.c)); w_out=intop2(abs(p)^2/(2*acpr.rho*acpr.c)); and trans=w_out/w_in. the inop1 and intop2 is intergations in incidence boundary and out boundary..

for most conditions, the trans smaller than 1, but in some simulation, the trans bigger than 1...

did some one encounter the same question? how you guys fix it?

best wishes...

Kyo

1 Reply Last Post 13.08.2012, 08:54 GMT-4
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Hello Yong LI

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Posted: 1 decade ago 13.08.2012, 08:54 GMT-4
Hi Yong Li,

Did you succeed in resolving the issue yet? If yes what was the explanation?
If not, and you are still interested in it, please attach your .mph file.
I will take a look into it.

Regards,
Joe
Hi Yong Li, Did you succeed in resolving the issue yet? If yes what was the explanation? If not, and you are still interested in it, please attach your .mph file. I will take a look into it. Regards, Joe

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