http://www.k-wave.org/forum/topic/question-about-shear-wave-propagation-examples Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 06:44:37 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/question-about-shear-wave-propagation-examples#post-4823 Tue, 04 Nov 2014 09:23:31 +0000 Bradley Treeby 4823@http://www.k-wave.org/forum/ <p>Hi Yu,</p> <p>If you want to define a pressure source, you must assign it to all components of the normal stress, i.e., in 2D <code>source.sxx = -p</code> and <code>source.syy = -p</code>. You can take a look at the m-file for the <a href="http://www.k-wave.org/documentation/example_ewp_shear_wave_snells_law.php">Shear Waves And Critical Angle Reflection Example</a>.</p> <p>It's also a good idea to filter your input signal using <code>filterTimeSeries</code> to make sure that the source doesn't contain frequencies not supported by the computational grid. </p> <p>Brad. </p> http://www.k-wave.org/forum/topic/question-about-shear-wave-propagation-examples#post-4822 Mon, 03 Nov 2014 18:50:40 +0000 firetripper 4822@http://www.k-wave.org/forum/ <p>1. In "example_ewp_layered_medium.m", how to define an explosive source. the example define initial pressure using "source.p0", but did not define how this pressure will change with time.</p> <p>2. I want to define a time varying stress source (6 cycles of the rectangular wave). Below is the code, can you point out whether my code is right?<br /> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++<br /> disc_magnitude = 0; % [Pa]<br /> disc_x_pos = 128; % [grid points]<br /> disc_y_pos = 128; % [grid points]<br /> disc_radius = 5; % [grid points]<br /> source.s_mask = makeDisc(Nx, Ny, disc_x_pos, disc_y_pos, disc_radius);</p> <p>% define a time varying pressure source<br /> source_mag = 5;</p> <p>t=0:1e-6:1000e-6;<br /> number_t=length(t);<br /> signal=zeros(1,number_t);</p> <p>fs_rec=1e6;<br /> t_rec = -90e-6:1/fs_rec:90e-6;<br /> w = 30e-6;<br /> y = rectpuls(t_rec,w);<br /> number_y=length(y);</p> <p>for i=1:6<br /> signal_temp((i-1)*number_y+1:i*number_y)=y;<br /> end<br /> signalonecycle=signal_temp(59:end);<br /> number_signalonecycle=length(signalonecycle);<br /> signal(1:number_signalonecycle)=signalonecycle;<br /> source.sxx = source_mag*signal;<br /> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++<br /> Thanks,<br /> Yu </p>