http://www.k-wave.org/forum/topic/sourcep Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 01:42:49 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/sourcep#post-5616 Fri, 29 Jul 2016 01:02:42 +0000 bencox 5616@http://www.k-wave.org/forum/ <p>Good question. Sources in k-Wave can raise non-trivial issues, but if you want a one-word answer, it is dx^2 not 1 m^2. For example, a pressure source of p Pascals applied evenly over a plane of M*M pixels of size dx^2, (in other words a total force of p*M^2*dx^2 Newtons) will be approximated well by using a weight of p at each source point.</p> <p>There is another aspect to be aware of. For initial pressure distributions, defined using <code>source.p0</code>, or sufficiently long time-varying sources, defined using <code>source.p</code>, the units will stay consistent. So if <code>source.p0</code> or <code>source.p</code> are defined in Pascals, then the measured signal will also be in Pascals. However, if the duration of the time-varying source is too short - comparable to <code>dx/medium.sound_speed</code> then the measured amplitude will be lower than expected. If this is your situation I can explain further, but it may take quite a long post.</p> <p>Also remember that when applying an initial pressure distribution, the resulting wave travels both outward and inward (or both left and right in the 1D case), so a factor of 2 may be required, depending on what you are trying to model.</p> <p>Hope that helps,<br /> Ben </p> http://www.k-wave.org/forum/topic/sourcep#post-5585 Fri, 08 Jul 2016 19:50:22 +0000 maryam.parto 5585@http://www.k-wave.org/forum/ <p>Hi<br /> I want to know that the pressure I define for a source point is force applied over an area of one meter squared or an area of one dx squared?<br /> Thanks for your attention. </p>