A Multiscale Euler–Lagrange Model for High-Frequency Cavitation Noise Prediction

To simulate the microscale bubble distribution and its effect on high-frequency cavitation noise, we present a two-way transition and coupling Euler–Lagrange model. The model accounts for both cavity fission and environmental nucleation as sources of microscale bubbles, which are limited in the traditional mesh-based Euler models. We evaluate the model with the experimental data of truncated NACA0009 hydrofoil as well as the measured bubble size distributions, showing satisfactory results for velocity distribution, cavity patterns, and power law scalings of bubble size. Based on an acoustic analogy, we find that the model produces sound waves with smaller wavelengths and higher frequencies than the Euler model, which are mainly attributed to two factors: (1) microscale bubbles with high natural frequency and (2) intense multiple cavity collapse/rebound behavior. This model is promising for predicting the full-spectrum of cavitation noise.