http://www.k-wave.org/forum/topic/acoustic-density-is-divided-into-cartesian-components Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 03:10:04 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/acoustic-density-is-divided-into-cartesian-components#post-5943 Tue, 23 May 2017 10:03:05 +0000 ZHANG Fan 5943@http://www.k-wave.org/forum/ <p>Hi Brad,</p> <p>Thank you very much for your reply. I have read the user manual and figured it out.</p> <p>But now I have another question. In the Sec.2.4 Table 2.1, it said that the outputs for both pressure and velocity are offset by △t/2 relative to the inputs. However, according to the discrete equations, I think it should be △t rather than △t/2. Could you please help me confirm it?</p> <p>Thanks!</p> <p>Best,<br /> Fan </p> http://www.k-wave.org/forum/topic/acoustic-density-is-divided-into-cartesian-components#post-5933 Sun, 21 May 2017 15:53:53 +0000 Bradley Treeby 5933@http://www.k-wave.org/forum/ <p>Hi Fan,</p> <p>The components are divided based on the vector acoustic particle velocity (see the equations in Sec. 2.4 in the manual). The total density is then given by the sum of the three components. It's not correct that rho_x = rho_y = rho_z = rho / 3.</p> <p>Brad. </p> http://www.k-wave.org/forum/topic/acoustic-density-is-divided-into-cartesian-components#post-5930 Sun, 21 May 2017 09:00:08 +0000 ZHANG Fan 5930@http://www.k-wave.org/forum/ <p>Hi everyone,</p> <p>The acoustic density (which is physically a scalar quantity) is articially divided into Cartesian components to allow an anisotropic perfectly matched layer to be applied, i.e.ρ=ρx+ρy+ρz。</p> <p>Could someone tell me that how the density is divided into three components? Is ρx=ρy=ρz=1/3ρ？</p> <p>Thanks in advance!</p> <p>Best,<br /> Fan </p>