NTOU Low Background Noise Large Cavitation Tunnel

This cavitation tunnel was established in 2001 The test section of NTOU large cavitation tunnel The overview of NTOU large cavitation tunnel

The test section has the following characteristics： The main characteristic of this tunnel is its very low background noise. The interaction between ship hull and propeller, and the propeller induced pressure fluctuation and underwater acoustic field can be measured. The test section has the following characteristics： 10.0meter in length, 2.60 meter in breadth and 1.50 meter in height. The maximal test speed is up to 12.15m/s at 86% output of the main motor. The maximal allowable working pressure at the center line of test section is 240kpa, and minimal is 20kpa. An anechoic acoustic chamber, 8.2 m in length, 2.2m in breadth and 1.77m in height, is located beneath the test section. The background noise of NTOU large cavitation tunnel measured in anechoic acoustic chamber in 1/3 octave bands spectrum at 6m/s velocity in the test section is lower than that in Baltic sea.

Inside layout of sound absorbing material in anechoic chamber beneath test scetion with hydrophone Signal conditioning Plate for hydrophone array

The background noise of NTOU large cavitation tunnel measured in anechoic acoustic chamber in 1/3 octave bands spectrum at 6m/s velocity in the test section

A full-scaled torpedo was tested in NTOU large cavitation tunnel

The contra-rotating propeller cavitation of a full-scaled torpedo has been observed in NTOU large cavitation tunnel

A research vessel shop model installed in test section of NTOU large cavitation tunnel. The test items include underwater noise, cavitation, and exciting force on the stern.

The propeller cavitation of a research vessel photographed from the ship model inside

A military ship with endplate propeller has been tested in NTOU large cavitation tunnel with excellent tip vortex cavitation inception

The cavitation phenomena of two propellers of a container ship model tested at NTOU Large Cavitation tunnel

Experiments Models Experiments Underwater vehicles Force / pressure Submarines (full scale) Torpedoes Supercavitating headforms Surface Ship: military / commercial with different types of propellers / appendages High speed train Experiments Force / pressure Exciting forces Cavitation Acoustics Flow visualization

Numerical Simulations Hydrodynamics: Propeller design: Lifting Line / Lifting Surface Analysis: RANS Propeller pressure fluctuation induced by propeller unsteady sheet cavitation Coupled Potential Flow / Viscous Flow computations Acoustics: Prediction underwater noise induced by propellers Cavitating and non-cavitating, including ship hull scattering and free surface effects

The investigation of a Energy saving Rudder for a container ship

Cavitation observation of full-scaled gear case at condition： Yaw angle 3∘，test speed 10m/s，σ=0.40，test pressure 28.12kPa NTOU large cavitation tunnel