k-Wave User Forum » Topic: Best way to simulate more than two layered materials in 2D

k-Wave User Forum » Topic: Best way to simulate more than two layered materials in 2D http://www.k-wave.org/forum/topic/best-way-to-simulate-more-than-two-layered-materials-in-2d Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 23:32:17 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://www.k-wave.org/forum/search.php buagciar on "Best way to simulate more than two layered materials in 2D" http://www.k-wave.org/forum/topic/best-way-to-simulate-more-than-two-layered-materials-in-2d#post-5381 Thu, 11 Feb 2016 18:38:33 +0000 buagciar 5381@http://www.k-wave.org/forum/ thank you!!! i can not figure this out, wokr for me! MUMiles on "Best way to simulate more than two layered materials in 2D" http://www.k-wave.org/forum/topic/best-way-to-simulate-more-than-two-layered-materials-in-2d#post-5195 Wed, 05 Aug 2015 18:18:26 +0000 MUMiles 5195@http://www.k-wave.org/forum/ Solved! I was going about this wrong. The correct way is to define your grid and then use: <code>medium.sound_speed_compression = medium.sound_speed_compression + 5000*makeDisc(Nx, Ny, Nx/2 ... etc</code> MUMiles on "Best way to simulate more than two layered materials in 2D" http://www.k-wave.org/forum/topic/best-way-to-simulate-more-than-two-layered-materials-in-2d#post-5194 Wed, 05 Aug 2015 17:37:12 +0000 MUMiles 5194@http://www.k-wave.org/forum/ Thanks Anthony, that did the trick! As far as using makeDisc I am still a little confused. I can populate my grid points for a material but when I try to define a disc in the center the plot just becomes "grayed out". Here is how I am trying to define different material parameters for a disc in the center: <pre><code>medium.sound_speed_compression = 5000*makeDisc(Nx, Ny, Nx/2, Ny/2, 2, 'true'); medium.sound_speed_shear = 2000*makeDisc(Nx, Ny, Nx/2, Ny/2, 2); medium.density = 6000*makeDisc(Nx, Ny, Nx/2, Ny/2, 2);</code></pre> Anthony on "Best way to simulate more than two layered materials in 2D" http://www.k-wave.org/forum/topic/best-way-to-simulate-more-than-two-layered-materials-in-2d#post-5185 Fri, 31 Jul 2015 08:36:30 +0000 Anthony 5185@http://www.k-wave.org/forum/ Hi MUMiles, First of all, you have a <code>3/Nx</code> instead of <code>Nx/3</code>. Then, if you look at the order of your material definition, the third one comprises (and though erases) the second one. Try <code>2*Nx/3</code>, and it will work ;-) <code>makeDisc</code> will help you for the circles. Anthony MUMiles on "Best way to simulate more than two layered materials in 2D" http://www.k-wave.org/forum/topic/best-way-to-simulate-more-than-two-layered-materials-in-2d#post-5183 Fri, 31 Jul 2015 00:28:51 +0000 MUMiles 5183@http://www.k-wave.org/forum/ Hello, First off thank you so much for offering this package free of charge. I am trying to simulate more than two layers of elastic/viscoelastic materials and am running into a problem when coding more than two layers. Here is the general process I am using: <blockquote> % Define properties of the first layer (FOAM) medium.sound_speed_compression = 2278*ones(Nx, Ny); % [m/s] medium.sound_speed_shear = 30*zeros(Nx, Ny); % [m/s] medium.density = 1265*ones(Nx, Ny); % [kg/m^3] % Define properties of the second layer (Steel) medium.sound_speed_compression(Nx/2:end, :) = 5164; % [m/s] medium.sound_speed_shear(Nx/2:end, :) = 2164; % [m/s] medium.density(Nx/2:end, :) = 7500; % [kg/m^3] % Define properties of the third layer (PMMA) medium.sound_speed_compression(3/Nx:end, :) = 11663; % [m/s] medium.sound_speed_shear(Nx/3:end, :) = 1663; % [m/s] medium.density(Nx/3:end, :) = 11185; % [kg/m^3] etc... </blockquote> But it seems as though I always end up with just two materials. Any insight into what I'm doing wrong is greatly appreciated. Also, it there a way to make the layers circular? Like if I wanted to take a cross section of a sphere in the center. My problem involves coated spheres. Thanks!