Numerical Study on Flow Noise Characteristics of Underwater Vehicles With Different Rudder Layouts

Abstract Flow noise of underwater vehicles has always been one of the important issues considered in the design and application of underwater vehicles. Interaction between rudders and the flow field has prominent influence on its noise characteristics. To improve the maneuverability of the underwater vehicle, different rudder layouts generally are designed and employed. However, their effects on the flow noise characteristics should be investigated. The key objective of present study is to analyze the flow field and the flow noise of the self-propulsion underwater vehicle with cross rudders and X rudders using Computational Fluid Dynamics (CFD), where the Suboff submarine and E1619 propeller models are selected. The numerical simulations are carried out based on LES turbulence model combined with the Ffowcs Williams–Hawkings (FW-H) equations. The flow noise calculation is very sensitive to the initial conditions. Hereby, it is necessary to ensure that the turbulence should be fully developed before the evaluation of noise. First, steady RANS is used to calculate the steady flow field. Results of the resistance and pressure distribution are compared with experimental data, to validate present numerical method. Then taking the steady flow field results as the initial conditions, the unsteady simulation of the flow field and the flow noise is calculated by using LES turbulence model and the FW-H equation. Circular monitoring probes are set up within the cross-section of the stern rudder to record the time varying results of e sound pressure. By comparing the sound pressure level at the cross section of the rudder, the influence of propeller is greater than that of rudder layouts.