アプリケーションギャラリ

This tutorial studies the propagation of high intensity focused ultrasound (HIFU) though a tissue phantom. HIFU is used in many different biomedical applications such as thermal ablation of tumors, transcranial HIFU surgery, shock wave lithotripsy, etc. A HIFU transducer typically contains a focusing lens that makes the emitted ultrasonic signal reach the highest intensity within a focal zone. When the emitted signal has a sufficiently high amplitude, nonlinear effects become significant, which results in the generation of the higher-order harmonics during the propagation of the signal.

The nonlinear propagation of a HIFU signal is modeled using the Nonlinear Pressure Acoustics, Time Explicit physics interface. In this example, the signal amplitude at the source location is enough for the generation of higher-order harmonics, but not high enough for the formation of shocks. The emitted signal is a tone burst pulse that occupies only a limited part of the computational domain on its way. Adaptive Mesh Refinement is used for automatic remeshing following the signal propagation. The mesh is fine enough to resolve the higher-order harmonics where it is required.