Cavitation Tunnel

For propeller tests and the study of forces on rudders, fins, submerged bodies, hydrofoils and cable fairings, Oceanic cost-effectively meets its clients needs with the Cavitation Tunnel. The cavitation tunnel features: 0.5 square working section; 0.1-2.0 ATM pressure range; 10m/sec flow speed; laser doppler velocimeter; and propeller and load dynamometers. These features make the facility ideal for a range of low-cost projects, including solving a warship noise problem and evaluating the performance of a seismic device. Testing can include: the effects of surface roughness on appendage performance and sensitive measuring devices; and determining lift and/or drag loads for any appendage model. Also, detailed flow measurements can be made using a laser doppler velocimeter.

Instrumentation and Equipment:

• Propeller Thrust and Torque Dynamometer (sealed strain gauge type mounted between propeller and first shaft bearing; ±900N thrust range; ±45Nm torque range)
  
• 6-Component Force Dynamometer (mounted in test-section window)
  
• Removable Propeller Shaft (allows full access to test section for testing models other than propellers)
  
• Laser Doppler Velocimeter (computer-controlled traverse)
  
• Oxygen Sensor (provides gas content measurements for proper cavitation scaling)
  
• Vacuum System (5-minute pump down to required pressure)
  
• Differential Pressure Transducers (flow and pressure measurements)
  
• Quick-release Poly-carbonate Windows (allow easy access to test section for model changeovers; provide excellent visibility for monitoring experiments)
  
• Strobe Lights; Photographic and Video Equipment
  
• Data Acquisition System (16-bit resolution)
  
• Computer-control System (allows for precise control of all propeller, flow, pressure and filtration functions)

Applications:

• Assessment of Propeller and Duct Performance
  
• Flow Visualization and Determination of Drag Characteristics for Various Appendages
  
• Cavitation Studies
  

Tests Performed:

• Propeller Tests in Uniform and Non-uniform Flows
  
• Measurement of Propeller Loads in Obstructed Flows
  
• Determination of Cavitation Effects on Propeller Performance
  
• Assessment of Cavitation Erosion
  
• Measurements of Cavitation Inception and Desinence
  
• Assessment of Duct Thrust/Drag Characteristics
  
• Force Measurement on Rudders, Fins, Struts, Cable Fairings, and Other Appendages
  
• Flow Visualization on Submerged Bodies
  
• Surface Roughness Studies

Related Projects:

• Assessment of Propeller Blade Root Fillet Design. - Tests investigated the effects of blade root fillet geometry on cavitation performance for a series of two dimensional models representing the blade root region of the Canadian Tribal Class destroyer propellers.
  
• Propeller Nozzle Evaluations - Comparative tests were completed to assess the performance of a novel nozzle design relative to the standard Nozzle No. 37.
  
• Assessment of Cable Fairing Hydrodynamic Performance - Various surface roughness treatments for turbulence stimulation were investigated in order to evaluate the hydrodynamic performance of various splitter plates, fairings and circular cylinders.
  
• Cavitation Erosion on a Model Ice-Class Propeller in Blocked Flow - Soft paint films were used to assess the likelihood of damaging erosion on a 200 mm diameter model of an open, fixed pitch propeller. Tests were conducted over a range of advance coefficients and with varying degrees of blockage.
  
• Cavitation Erosion in Blocked Flow with a Ducted Ice-Class Propeller - Soft paint films were used to assess the likelihood of damaging erosion on a 200 mm diameter model of a ducted, controllable pitch propeller. Tests were conducted over a range of advance coefficients and with varying degrees of blockage. The nozzle was made from polycarbonate material in order to allow for unsurpassed cavitation observation during testing.

Download Specification Sheet