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PML is reflecting acoustic wave

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Hello everyone,

PML is not absorbing acoustic waves and it's causing some unphysical reflections, is there any experienced guy with perfectly matched layer here? I'm trying to compute scattered wave off an abject which is put in a background standing wave.

Kind regards Jason


2 Replies Last Post Oct 1, 2020, 7:54 a.m. EDT
Dave Greve Certified Consultant

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Posted: 4 years ago Sep 30, 2020, 4:13 p.m. EDT

They really should call them IMperfectly matched layers.

You should check the settings (wave velocity), the thickness, and the meshing (mapped mesh with ~5 elements preferred). And at least in emw there are some additional parameters that can be adjusted.

If it's critical set up a separate simulation to quantify the amount of reflected wave.

They really should call them IMperfectly matched layers. You should check the settings (wave velocity), the thickness, and the meshing (mapped mesh with ~5 elements preferred). And at least in emw there are some additional parameters that can be adjusted. If it's critical set up a separate simulation to quantify the amount of reflected wave.

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Posted: 4 years ago Oct 1, 2020, 7:54 a.m. EDT
Updated: 4 years ago Oct 1, 2020, 8:31 a.m. EDT

They really should call them IMperfectly matched layers.

You should check the settings (wave velocity), the thickness, and the meshing (mapped mesh with ~5 elements preferred). And at least in emw there are some additional parameters that can be adjusted.

If it's critical set up a separate simulation to quantify the amount of reflected wave.

Hi Dave,

I need to have a non-reflecting boundary in my thermoviscous acoustic simulation, but it seems this so-called "PML" is not working the way it should. in my simulation pml geometry is a rectangle surrounding a partcle and I want pml to absorb scattered wave off the particle (which are spherical-shaped waves) but it's not working. You think it might be due to the scatterd way angle to PML?

Kind regards

>They really should call them IMperfectly matched layers. > >You should check the settings (wave velocity), the thickness, and the meshing (mapped mesh with ~5 elements preferred). And at least in emw there are some additional parameters that can be adjusted. > >If it's critical set up a separate simulation to quantify the amount of reflected wave. Hi Dave, I need to have a non-reflecting boundary in my thermoviscous acoustic simulation, but it seems this so-called "PML" is not working the way it should. in my simulation pml geometry is a rectangle surrounding a partcle and I want pml to absorb scattered wave off the particle (which are spherical-shaped waves) but it's not working. You think it might be due to the scatterd way angle to PML? Kind regards

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