Cavitation Test |
Since a propulsion system is an essential part of any motorized
vessel, designers strive to ensure that it functions within its
intended operational envelope so that the vessel can complete
its mission. Additional demands on today's systems include the
need for quiet and vibration-free operation in order to meet stringent
habitability requirements. Cost-effective propulsor assessment
is offered by Oceanic using the Cavitation
Tunnel.
Baseline open water performance can easily be determined at atmospheric
pressure. By performing tests in a reduced pressure environment,
full-scale conditions can be simulated allowing test engineers
to assess the impact of cavitation on propulsor performance. Additionally,
soft film tests at reduced pressure to assess the presence of
severe cavitation impingement, can indicate the likelihood of
blade erosion which can lead to structural degradation of propellers.
Because the test section contains viewing ports, the opportunity
exists to conduct flow visualization
tests.
While propellers are examined most often, the cavitation tunnel
is also used to assess the performance of appendages such as nozzles,
rudders, stabilizer fins, fairings and brackets. Using sensitive
measuring devices, lift and/or drag loads can be determined for
any appendage model. The effects of surface roughness on appendage
performance have also been studied in past work. Detailed flow
field measurements can be made using a laser doppler velocimeter.
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.
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