http://www.k-wave.org/forum/topic/what-is-the-pysical-quantity-of-the-forcing-function Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 00:11:39 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/what-is-the-pysical-quantity-of-the-forcing-function#post-6888 Thu, 20 Jun 2019 22:25:59 +0000 Bradley Treeby 6888@http://www.k-wave.org/forum/ <p>That's correct - the mass source term in k-Wave is equivalent to a source term with a time derivative in the second order wave equation (see Eq. 2.9 in the manual V1.1). </p> <p>The source term in the code appears as in Eq. 2.17 (as a mass source). The user inputs are given in units of pressure, so it's scaled appropriately. </p> http://www.k-wave.org/forum/topic/what-is-the-pysical-quantity-of-the-forcing-function#post-6846 Fri, 10 May 2019 02:30:23 +0000 laughingrice 6846@http://www.k-wave.org/forum/ <p>I've been trying to match the k-wave simulation to a standard finite difference acoustic simulation with a Ricker wavelet forcing function.</p> <p>i.e solve u_tt - c^2 u_xx = f</p> <p>As Ricker is the second order time derivative of a Gaussian, the source pressure is a Gaussian. I tried using that for source.p which did not produce the same results. Looking at the governing equations defined in eq 2.8 in the user manual, what is defined as the pressure source term matches the mass source in that equation (d\rho/dt), and using that (the normalized time derivative of the Gaussian pressure source) does match the result of the finite difference simulations.</p> <p>I wanted to verify what does source.p actually define, a pressure source term as in the function help file and section 3.4 of the manual or a mass source term (flow of mass) as defined in section 2.2 of the manual.</p> <p>Thanks </p>