http://www.k-wave.org/forum/topic/introduction-of-negative-pressure-from-nowhere Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 22:34:33 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/introduction-of-negative-pressure-from-nowhere#post-8961 Fri, 24 Nov 2023 17:49:18 +0000 Bradley Treeby 8961@http://www.k-wave.org/forum/ <p>See <a href="http://www.k-wave.org/forum/topic/signal-emission-frequency#post-7962">this post</a> which might help explain what you see. </p> http://www.k-wave.org/forum/topic/introduction-of-negative-pressure-from-nowhere#post-8919 Mon, 25 Sep 2023 19:40:31 +0000 jjb7481 8919@http://www.k-wave.org/forum/ <p>Also worth noting, I have tried filtering my sources according to the automatic filtering k-wave does due to grid refinement limitations, and have verified that that automatic filtering is not the cause of the negative pressure. </p> http://www.k-wave.org/forum/topic/introduction-of-negative-pressure-from-nowhere#post-8918 Mon, 25 Sep 2023 19:37:22 +0000 jjb7481 8918@http://www.k-wave.org/forum/ <p>Hello,</p> <p>I am attempting to model a lithotripter, which typically consists of a source function that is entirely compression (all positive pressure). No matter the exact wave shape or source type, when I plug in such a source, the result always has a very strong rarefaction following the compression (introduction of negative pressure) AT the source itself. That is, the source function is not what the source outputs in k-wave. I have some physical and mathematical reasoning from acoustics textbooks for why this occurs but measurements do not show this phenomenon and so I would like to eliminate it. I would simply like the output of my sources to be what I plug in. Any ideas/assistance? </p>