PSpice modelling nonlinearity effects on ultrasonic waves

Nonlinearity is one of the phenomena that affect the ultrasonic wave during its propagation in a given medium. In the time domain the nonlinearity is seen as a variation of the phase velocity which leads to a distortion of the wave form that corresponds in the frequency domain to energy transfer from the fundamental frequency to the harmonic and among the harmonic themselves. Our previous work was axed on the modelling with the simulation tool PSpice of the absorption and the diffraction effects on the wave propagation. The aim of this paper is to introduce the PSpice implementation of the computational model of the nonlinear ultrasound propagation. We study first the plane wave distortion based on the Burgers' equation. Our PSpice model allowed studying the temporal profile of the ultrasonic wave during its propagation. The simulation results are compared to the analytical solution of the burgers' equation showing the validity of the model.