Numerical simulation of nonlinear wave propagation in thermoviscous fluids including dissipation

A recently developed finite element method for the numerical simulation of nonlinear sound wave propagation in thermoviscous fluids is presented. Based on the nonlinear wave equation as derived by Kuznetsov, typical effects associated with nonlinear acoustics like generation of higher harmonics and dissipation resulting from the propagation of a finite amplitude wave through a thermoviscous medium are covered. The method is verified by comparison with the well-known Fubini and Fay solutions for plane wave problems, where excellent agreement is found. As a practical application, a high intensity focused ultrasound source is considered. Measurements of the radiated pressure pulse at various distances from the source are compared with corresponding simulation results. The obtained good agreement demonstrates validity and applicability of the nonlinear finite element method.