A Two-Dimensional Hybrid Computational Acoustics Method to Predict the Far-Field Noises

Cylindrical shells are ubiquitous in aerospace, marine, and other navigational applications, where their acoustic radiation characteristics are crucial performance indicators. This paper addresses the far-field acoustic radiation problem of cylindrical shells by proposing a two-dimensional hybrid computational acoustic method. The hybrid approach innovatively combines a Linear Euler Equation (LEE) method to accurately capture near-field fluid and acoustic dynamics with the Ffowcs Williams-Hawkings (FW-H) equation to predict far-field noises. To validate the hybrid method's performance, the far-field noises emanating from both two-dimensional benchmark sound sources and a vibrating cylinder with a frequency range of 0-3000Hz in the air were calculated. Additionally, the hybrid approach analyzed experimental data on radiated noises from a cylindrical shell with a frequency range of 0-1000Hz in an anechoic chamber. The computational results indicate that the proposed hybrid method exhibits a 10% improvement in prediction accuracy for far-field noises compared to the FW-H method, and a 50% enhancement in computational efficiency compared to the LEE method. Therefore, it serves as a powerful tool in engineering applications.