Hydrodynamic noise research with a planing boat under acoustical free field conditions

A planing boat has been designed as a tool for research of hydrodynamic noise sources under acoustical free field conditions. The facility is used primarily for investigations of propeller cavitation noise in non-uniform wake flows. The objective of these tests is to disclose the influence of propeller design and wake fields upon cavitation noise. The operational test conditions are the same as for prototype surface ships. Compared to full scale the advance speed or Mach number are the same, but the Reynolds number is lower by the scale factor. The boat is equipped with several devices for observing and recording cavitation and noise. A small acoustic range with a suspended stationary hydrophone is used for recording the radiated far field noise of the test objects.