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2D plane wave using radiation boundary

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I am relatively new to COMSOL but I'd like to model 2 D plane wave with infinite boundary. Has anyone know how to do it? I want to use structural interaction module under Acoustic Module to simulate the interaction bet'n the device and the plane wave. Thanks in advance!

5 Replies Last Post Jun 21, 2010, 6:39 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago May 31, 2010, 2:20 a.m. EDT
Hi

Have you done the examples in the doc ? and the ones from the model libary ?
that really helps, Iagree it takes time, but still, it's the second quickest way to go on, for me the 1st boost you will get by the COMSOL 1-2 day courses, but not mopre than 1 per month, to allow you to play with the soft inbetween and absorb most of the knowledge needed

Have fun Comsoling
UIvar
Hi Have you done the examples in the doc ? and the ones from the model libary ? that really helps, Iagree it takes time, but still, it's the second quickest way to go on, for me the 1st boost you will get by the COMSOL 1-2 day courses, but not mopre than 1 per month, to allow you to play with the soft inbetween and absorb most of the knowledge needed Have fun Comsoling UIvar

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Posted: 1 decade ago May 31, 2010, 1:43 p.m. EDT
Yes, I have. The thing is if you create a 2-D rectangular box with radiation boundary on 3 of those and use one side as either normal acceleration or radiation source by applying p_in = exp(-i*(kx*x+ky*y) assuming that p_0 = 1 [Pa], you don't get plane wave due to Huygen's principle which assumes every point of the side is composed of many point and at each point acts as a sound source. However, if you use two sides which perpendicularly lined up with radiating source side as hard wall boundary, you get plane wave no problem.

What I want is not to use hard wall boundary as well as background field pressure either to come up with plane wave.

The reason is I want to see the interaction of the underwater acoustic sensor with the medium which sits in the infinite medium boundary since I do not want any disturbances with the boundary. Thanks!
Yes, I have. The thing is if you create a 2-D rectangular box with radiation boundary on 3 of those and use one side as either normal acceleration or radiation source by applying p_in = exp(-i*(kx*x+ky*y) assuming that p_0 = 1 [Pa], you don't get plane wave due to Huygen's principle which assumes every point of the side is composed of many point and at each point acts as a sound source. However, if you use two sides which perpendicularly lined up with radiating source side as hard wall boundary, you get plane wave no problem. What I want is not to use hard wall boundary as well as background field pressure either to come up with plane wave. The reason is I want to see the interaction of the underwater acoustic sensor with the medium which sits in the infinite medium boundary since I do not want any disturbances with the boundary. Thanks!

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Posted: 1 decade ago Jun 20, 2010, 3:07 a.m. EDT
Hi every body.
I have one question about comsol. I need to solve acoustic pressure and bioheat equation simultaneously in comsol. At first I solve acoustic pressure with high frequency then I solve bioheat equation with source term (this source term relate acoustic pressure with bio heat equation). I heard that whenever frequencies are very high (about MHz) it is better to use "Ultraweak variational formulation”. But when I set this "Ultraweak variational formulation” On, I don’t know why comsol couldn’t obtain any result for bioheat equation. I don’t know may be it couldn’t include pressure in source term.
Do you know why?


Thank you
With Best Regards,
Fatemeh Sharifi
Hi every body. I have one question about comsol. I need to solve acoustic pressure and bioheat equation simultaneously in comsol. At first I solve acoustic pressure with high frequency then I solve bioheat equation with source term (this source term relate acoustic pressure with bio heat equation). I heard that whenever frequencies are very high (about MHz) it is better to use "Ultraweak variational formulation”. But when I set this "Ultraweak variational formulation” On, I don’t know why comsol couldn’t obtain any result for bioheat equation. I don’t know may be it couldn’t include pressure in source term. Do you know why? Thank you With Best Regards, Fatemeh Sharifi

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Posted: 1 decade ago Jun 21, 2010, 5:53 a.m. EDT
I don't know the specifics of your job but before others who do come forward to reply, just double check that you are storing the result of pressure calculation in solver manager. This is a general requirement in comsol and necessary to carry forward the results of preceding simulation to the following one.
I don't know the specifics of your job but before others who do come forward to reply, just double check that you are storing the result of pressure calculation in solver manager. This is a general requirement in comsol and necessary to carry forward the results of preceding simulation to the following one.

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Posted: 1 decade ago Jun 21, 2010, 6:39 a.m. EDT
I don't know the specifics of your job but before others who do come forward to reply, just double check that you are storing the result of pressure calculation in solver manager. This is a general requirement in comsol and necessary to carry forward the results of preceding simulation to the following one.
I don't know the specifics of your job but before others who do come forward to reply, just double check that you are storing the result of pressure calculation in solver manager. This is a general requirement in comsol and necessary to carry forward the results of preceding simulation to the following one.

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