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Hydrodynamic Noise Characteristics of a Marine Current Turbine

A kind of marine current turbines was established to provide energy for underwater mooring platforms (UMP) to lengthen its service life in the ocean. However, it was found there was loud noise during the experimental tests in the towing tank. Considering the working conditions in the ocean, the hydrodynamic noise of the marine current turbines has to be emphasized to reduce the harm to the marine organisms and the threat to the high-precision mechanical equipment. However, the detailed acoustic performances of marine current turbine haven't been evaluated though several researchers have realized the harm of the released noise to the marine ecological environment. In the article, large eddy simulations (LES) and Ffowcs Williams and Hawkings (FW-H) acoustic wave equation are applied for the calculation of radiated noise of the marine current turbine. The noise characteristics in near acoustic field and in far acoustic field are studied, individually. The results showed that the transmission characteristics of the hydrodynamic noise are totally different in the three chosen planes, and the noise energy transmits easily in the axis direction of the turbine. The results in this paper could provide some guidance for the noise characteristics investigation of the marine current turbine, and it could also help to reduce the harm to the ocean environment.