http://www.k-wave.org/forum/topic/resize-simulation-grid-how-do-correct-choice Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 03:09:00 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/resize-simulation-grid-how-do-correct-choice#post-5045 Wed, 15 Apr 2015 19:25:52 +0000 Bradley Treeby 5045@http://www.k-wave.org/forum/ <p>Hi Gg,</p> <p>In general, your simulations will be fastest if the grid dimensions including the PML have small prime factors. This is because the simulations are based heavily on the FFT. So 2^N will be the best, but there are also lots of other suitable sizes that also have small prime factors. There are some details about this in Sec. 3.2 in the k-Wave manual.</p> <p>Brad. </p> http://www.k-wave.org/forum/topic/resize-simulation-grid-how-do-correct-choice#post-5041 Sun, 12 Apr 2015 15:54:00 +0000 gigi 5041@http://www.k-wave.org/forum/ <p>Dear All,<br /> Hi,<br /> I would like to change the size of the grid to use transducers of different dimension.</p> <p>For example, I would like to resize the grid of the example example_us_bmode_linear_transducer.m to use a 192 elements transducer instead a 32 elements transducer:</p> <p><code>%physical properties of the transducer with 192 elements</code><br /> <code>transducer.number_elements = 192; % total number of transducer elements</code><br /> <code>transducer.element_width = 2; % width of each element [grid points]</code><br /> <code>transducer.element_length = 24; % length of each element [grid points]</code><br /> <code>transducer.element_spacing = 0; % spacing (kerf width) between the elements [grid points]</code><br /> <code>transducer.radius = inf; % radius of curvature of the transducer [m]</code></p> <p>Is it correct to set grid as below?</p> <p><code>% set the size of the perfectly matched layer (PML)</code><br /> <code>pml_x_size = 20; % [grid points]</code><br /> <code>pml_y_size = 10; % [grid points]</code><br /> <code>pml_z_size = 10; % [grid points]</code></p> <p><code>% set total number of grid points not including the PML</code><br /> <code>Nx = 156 - 2*pml_x_size; % [grid points]</code><br /> <code>Ny = 768 - 2*pml_y_size; % [grid points]</code><br /> <code>Nz = 128 - 2*pml_z_size; % [grid points]</code></p> <p>Could be better to put Ny equal a power of 2 (es. Ny=2^9)?</p> <p>Is there a general rule to manage grid sizing ? </p> <p>Thank you a lot</p> <p>Gg </p>