Investigation into the Hydrodynamic Noise Characteristics of Electric Ducted Propeller

Ducted propeller is a kind of special widely used in unmanned underwater vehicles, its flow characteristics and hydrodynamic noise are very important for marine environmental protection equipment concealment. The hybrid techniques based on the acoustic analogy theory adopted present study to calculate unsteady field sound ducted propeller. full scale filed hydro-acoustic sources propulsion system simulated by Detached-Eddy computational fluid dynamics (CFD) method. Hydrodynamic calculated FWH equation CFD results. frequency domain directivity pressure level at different monitoring points analyzed four navigational speeds. results show that speed inflow condition play roles structure radiated noise. Under fixed impeller rotational speed, efficiency increases first then decreases with raise speed. maximum errors thrust power between simulation experiment values 0.5% 0.1% respectively, which means DES numerical method has high credibility calculating source. At 2000 r/min, best state distribution 1.54 m/s, corresponding highest condition. presents dipole characteristic all working conditions, obvious blade passing frequency, multiple presented; most contribution also concentrated below times frequency. total smallest optimal (the m/s). low increase amplitude becomes larger. This indicates component turbulent more research focuses analyzing relationship energy loss wake level, it found vortex tail makes certain conclusions could provide some reference performance evaluation reduction optimization design as well improvement UUV stealth performance.