Cavitation tunnels

CTO S.A. designs, builds and supplies cavitation tunnels tailored to individual customer requirements.

A cavitation tunnel is an experimental facility used to test the hydrodynamic behaviour of bodies submerged in flowing water. Cavitation tunnels are used in essentially the same way and on the same physical principles as low velocity closed type wind tunnels. Such tunnels allow the direct study of cavitation phenomena that cannot be carried out in a wind tunnel.

LARGE CAVITATION TUNNEL

There are several “large” cavitation tunnels in the world. CTO can boasts the design of the seventh largest cavitation tunnel in the world, located at the Istanbul Technical University in Turkey.

FLOW VISUALIZATION

Cavitation tunnels are widely used for flow visualization studies and are often used instead of wind tunnels to perform measurements because techniques such as PIV (Particle Image Velocimetry) are easier to implement in water. Observation, photo and video recording in cavitation tunnels is much more detailed than in wind tunnels.

THE REYNOLDS NUMBER

For the equivalent Reynolds number, the results are valid whether the airborne vehicle model is air tested or the air vehicle model is water tested.

STANDARD TESTS

A set of standard model tests and experimental tests that can be carried out in a cavitation tunnel are:

• cavitation model tests of propeller performed in a uniform velocity field, including determination of hydrodynamic characteristics,
• cavitation model testing of propellers and rudders in a simulated in-service velocity field,
• model tests of the impact of a working propeller on the surface of the stern part of the hull,
• model studies of hydroacoustic effects of propeller operation.

STANDARD TESTS continued

• cavitation model testing of supporting airfoils,
• experimental studies of the initiation of cavitation,
• research on the interaction and transformation of various forms of cavitation (bubble, laminar, cloud and vortex),
• searching for correlation between cavitation and hydroacoustic emission, testing the influence of flow parameters (e.g. the boundary layer) and flowing bodies on the development of cavitation.

CTO S.A. standard in the design of cavitation tunnels is to ensure a stable flow in the section free from cavitation.

Contact one of our engineers for more information and a quote.

The CTO offer also includes:

• a hydroacoustic chamber allowing to determine the noise level generated by the tested propeller
• a set of high-speed cameras allowing for the observation and recording of cavitation,
• laser anemometer for measuring the velocity field;
• advanced control system,
• Integrated Data Acquisition System (DAS),
• a wide range of measuring equipment used in modern model tests.

See catalogue cards Cavitation tunnels and Measuring equipment.