2D Numerical Modeling for Transducers with Combined Pseudospectral and Finite Difference Methods: Application to High Frequency Linear Arrays

摘要

A 2D numerical model based on a hybrid finite-difference (FD) and pseudospectral (PS) method adapted to high frequency linear arrays is presented. This model, coupled with the DREAM toolbox, was used to simulate the 1-way radiation pattern in water of a 50 MHz linear array with 64 elements (at a focal distance of 10 mm). The influence of several parameters of the internal structure of the array on the radiation pattern was studied. The variation of element widths, kerf widths and kerf depths was evaluated on the main properties of the pressure field (i.e. spatial resolutions, sensitivity and depth of field) in the focal zone. These simulations were performed using experimental data previously measured for materials used and in particular for the PZT piezoelectric thick film. Results show that a trade-off can be found between the technological aspects (width of elements and kerf) and performance of the array. Finally, a kerfless configuration was evaluated and it is shown that this is also a viable option.