Modelling nonlinear ultrasound propagation in absorbing media using the k-Wave toolbox: experimental validation

The simulation of nonlinear ultrasound waves in biological tissue has a number of important applications. However, this is a computationally intensive task due to the large domain sizes required for many problems of practical interest. Recently, an efficient full-wave nonlinear ultrasound model was developed and released as part of the open source k-Wave Toolbox. Here, this model is validated using a series of experimental measurements made with a linear diagnostic ultrasound probe and a membrane hydrophone. Measurements were performed in both deionised water and olive oil, the latter exhibiting power law absorption characteristics similar to human tissue. Steering angles of 0° and 20° were also tested, with propagation distances on the order of hundreds of acoustic wavelengths. The simulated and experimental results show a close agreement in both the time and frequency domains. These results demonstrate the quantitative validity of performing nonlinear ultrasound simulations using the k-Wave toolbox.