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Trouble with pressure wave input (Acoustic Module: Transient Analysis)

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I have constructed a 1D model of a pressure wave propogating in the positive direction and then reflecting off the boundary.

To supply the pressure wave, I have used the radiation condition with a pressure that is dependent on time and is defined as:

p_in = p0*cos(k*x-omega*t)

p0- inlet pressure amplitude (2 Pa), k-wave number, omega-angular frequency

My issue is that the pressure wave actually supplied varies with an amplitude 0 < A < 4. I was expecting the pressure amplitude to vary as -2 < A < 2...

Is there a simple explanation for this?

I have attached to file for reference.

Thank you,

-Jon


1 Reply Last Post Nov 25, 2010, 3:23 p.m. EST
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Hello Jonathan MacDonald

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Posted: 1 decade ago Nov 25, 2010, 3:23 p.m. EST
Have you thought about the standing wave? I mean since you applied the boundary condition as reflecting on one end, you'd get constructive wave which doubles the amplitude.
Have you thought about the standing wave? I mean since you applied the boundary condition as reflecting on one end, you'd get constructive wave which doubles the amplitude.

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