Emerson Cavitation Tunnel

Last updated
Emerson Cavitation Tunnel
Emerson Cavitation Tunnel.jpg
Emerson Cavitation Tunnel
General information
Type Educational
LocationNewcastle University Marine Station, Blyth, United Kingdom
Coordinates 55°07′30″N1°29′52″W / 55.124894°N 1.497748°W / 55.124894; -1.497748 Coordinates: 55°07′30″N1°29′52″W / 55.124894°N 1.497748°W / 55.124894; -1.497748
Completed1949, refurbished and relocated in 2017
Owner Newcastle University

The Emerson Cavitation Tunnel is a propeller testing facility that is part of the School of Engineering at Newcastle University.

Contents

Capabilities

The Emerson Cavitation Tunnel consists of a water circuit which flows in the vertical plane, within which propellers and other propulsion devices can be tested. The system is powered by a 300 kW (400 hp) pump, with a four-bladed impeller and can produce a maximum water velocity of 15.5 knots (28.7 km/h; 17.8 mph). The test area has a cross sectional area of 0.99 m2 (10.7 sq ft) allowing model propellers of up to 30 cm (12 in) in diameter to be tested. The pressure range of the tunnel can vary from a minimum of 7.6 kN/m2 to a maximum of 106 kN/m2. Cavitation numbers of 0.5 (minimum) to 23 (maximum) can be accommodated for. Measurements can be taken using a 3 Watt, water-cooled, Argon-ion laser, a hydrophone, and two dynamometers. A high-speed video camera is also attached with an imaging frequency of 1–10,000 frames per second.

Funding for the tunnel's equipment is raised by numerous organisations, including the Engineering and Physical Sciences Research Council (EPSRC) and the Scottish Universities of Glasgow and Strathclyde.

History

The tunnel was first established at the University in 1949 after being disassembled and transported from Pelzerhaken, Germany after the Second World War. The tunnel arrived at the University in 1947 and over the following few years the tunnel was heavily modified. The tunnel - which was originally designed to be operated in the horizontal plane - was converted into a vertical loop tunnel and the length was reduced by half. The original observation window was modified and two more added. Because of damage, a new impeller was constructed and numerous pieces of measuring equipment were added. This equipment included pitot tubes, a tachometer, stroboscopic lighting equipment, contact meters and a vacuum pump. The tunnel was connected to an electrical supply in 1949 and entered service late in 1950, after technical problems called for recalibration of some of the instruments. The Cavitation Tunnel was housed in Newcastle University's old boiler house, where it was originally reconstructed. That location was on King's Road in the middle of the University's city centre campus between the Armstrong building, the Student Union, the Arches and the Bedson building.

In 2016, the tunnel was moved from the Newcastle University city centre campus and taken to Poland, where it was fully refurbished before being brought back to the North East and installed in a new purpose-built research centre, Marine campus at Blyth.

The first research grant of £8,000 was awarded in 1950 for the testing of a new series of propellers, and was awarded by the Department of Scientific and Industrial Research (DSIR).

In the 1970s and 1980s, the tunnel was extensively modified and upgraded in order to improve the range of propellers that could be tested. The tunnel was also renamed to its current name, the Emerson Cavitation Tunnel after Dr Arnold Emerson, who was the tunnel superintendent and the driving force behind the upgrades.

Modifications were made to the tunnel during the 1980s. New computer-based data collection, interpretation and analysis technology has been added to aid with computational fluid dynamics. Data is also collected with the help of laser doppler anemometry (LDA) and phase doppler anemometry (PDA).

Location

The tunnel is now located at Newcastle University's Marine Campus at Blyth, Northumberland.

See also

Related Research Articles

Cavitation Formation of vapour-filled low-pressure voids in a liquid

Cavitation is a phenomenon in which rapid changes of pressure in a liquid lead to the formation of small vapor-filled cavities in places where the pressure is relatively low.

Propeller Device that transmits rotational power into linear thrust on a fluid

A propeller is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral, that when rotated performs an action which is similar to Archimedes' screw. It transforms rotational power into linear thrust by acting upon a working fluid such as water or air. The rotational motion of the blades is converted into thrust by creating a pressure difference between the two surfaces. A given mass of working fluid is accelerated in one direction and the craft moves in the opposite direction. Propeller dynamics, like those of aircraft wings, can be modelled by Bernoulli's principle and Newton's third law. Most marine propellers are screw propellers with helical blades rotating around an approximately horizontal axis or propeller shaft.

Outboard motor Self-contained propulsion system for boats

An outboard motor is a propulsion system for boats, consisting of a self-contained unit that includes engine, gearbox and propeller or jet drive, designed to be affixed to the outside of the transom. They are the most common motorized method of propelling small watercraft. As well as providing propulsion, outboards provide steering control, as they are designed to pivot over their mountings and thus control the direction of thrust. The skeg also acts as a rudder when the engine is not running. Unlike inboard motors, outboard motors can be easily removed for storage or repairs.

Supercavitation

Supercavitation is the use of a cavitation bubble to reduce skin friction drag on a submerged object and enable high speeds. Applications include torpedoes and propellers, but in theory, the technique could be extended to an entire underwater vessel.

Newcastle University university in Newcastle upon Tyne, United Kingdom

Newcastle University is a public research university in Newcastle upon Tyne in the North East of England. The university can trace its origins to a School of Medicine and Surgery, established in 1834, and to the College of Physical Science, founded in 1871. These two colleges came to form one division of the federal University of Durham, with the Durham Colleges forming the other. The Newcastle colleges merged to form King's College in 1937. In 1963, following an Act of Parliament, King's College became the University of Newcastle upon Tyne.

A ship model basin is a physical basin or tank used to carry out hydrodynamic tests with ship models, for the purpose of designing a new ship, or refining the design of a ship to improve the ship's performance at sea. It can also refer to the organization that owns and operates such a facility.

Pump-jet Marine propulsion system

A pump-jet, hydrojet, or water jet is a marine system that produces a jet of water for propulsion. The mechanical arrangement may be a ducted propeller, a centrifugal pump, or a mixed flow pump which is a combination of both centrifugal and axial designs. The design also incorporates an intake to provide water to the pump and a nozzle to direct the flow of water out of the pump.

Laser Doppler velocimetry Optical method of measuring fluid flow

Laser Doppler velocimetry, also known as laser Doppler anemometry, is the technique of using the Doppler shift in a laser beam to measure the velocity in transparent or semi-transparent fluid flows or the linear or vibratory motion of opaque, reflecting surfaces. The measurement with laser Doppler anemometry is absolute and linear with velocity and requires no pre-calibration.

Voith Schneider Propeller

The Voith Schneider propeller (VSP), also known as a cycloidal drive is a specialized marine propulsion system (MPS). It is highly maneuverable, being able to change the direction of its thrust almost instantaneously. It is widely used on tugs and ferries.

Impeller Rotor used to increase (or decrease in case of turbines) the pressure and flow of a fluid or gas

An impeller or impellor is a rotor used to increase the pressure and flow of a fluid. It is the opposite of a turbine, which extract energy from, and reduces the pressure, of a flowing fluid.

Australian Maritime College maritime college in Tasmania, Australia

The Australian Maritime College (AMC) is a tertiary education institution based in Launceston, Tasmania, established by the Maritime College Act 1978 (Cth). Tertiary education is provided and organised by the University of Tasmania (UTAS) as the Australian Maritime College (AMC) at the University of Tasmania (AMC@UTAS). However the college's educational curriculum is governed by the independent AMC Board. The AMC is Australia's national centre for maritime education, training and research. It has two campuses located within 50 kilometres (31 mi) of each other in Northern Tasmania, each with different facilities and residence.

Axial-flow pump Type of pump consisting of a propeller in a pipe

An axial-flow pump, or AFP, is a common type of pump that essentially consists of a propeller in a pipe. The propeller can be driven directly by a sealed motor in the pipe or by electric motor or petrol/diesel engines mounted to the pipe from the outside or by a right-angle drive shaft that pierces the pipe.

Marine engineering Engineering of boats, ships, oil rigs or other marine vessel or structure

Marine engineering includes the engineering of boats, ships, oil rigs and any other marine vessel or structure, as well as oceanographic engineering or ocean engineering. Specifically, marine engineering is the discipline of applying engineering sciences, including mechanical engineering, electrical engineering, electronic engineering, and computer science, to the development, design, operation and maintenance of watercraft propulsion and on-board systems and oceanographic technology. It includes but is not limited to power and propulsion plants, machinery, piping, automation and control systems for marine vehicles of any kind, such as surface ships and submarines.

Water tunnel (hydrodynamic) hydrodynamic test facility

A water tunnel is an experimental facility used for testing the hydrodynamic behavior of submerged bodies in flowing water. It functions similar to a recirculating wind tunnel, but uses water as the working fluid, and related phenomena are investigated, such as measuring the forces on scale models of submarines or lift and drag on hydrofoils. Water tunnels are sometimes used in place of wind tunnels to perform measurements because techniques like particle image velocimetry (PIV) are easier to implement in water. For many cases as long as the Reynolds number is equivalent, the results are valid, whether a submerged water vehicle model is tested in air or an aerial vehicle is tested in water. For low Reynolds number flows, tunnels can be made to run oil instead of water. The advantage is that the increased viscosity will allow the flow to be a faster speed for a lower Reynolds number.

The University of Texas at Arlington Aerodynamics Research Center (ARC) is a facility located in the southeast portion of the campus operated under the Department of Mechanical and Aerospace Engineering. It was established in 1986 as part of an expansion of UTA's College of Engineering. The ARC contributes to the vision of UTA and the University of Texas System to transform the university into a full-fledged research institution. It showcases the aerodynamics research activities at UTA and, in its history, has established itself as a unique facility at a university level. The wind tunnels and equipment in the facility were mainly built by scouting for and upgrading decommissioned equipment from the government and industry. Currently, Masters and Ph.D. students perform research in the fields of high-speed gas dynamics, propulsion, and Computational fluid dynamics among other projects related to aerodynamics.

Dr. William B. Morgan is an American naval architect and renowned expert in propeller design.

A rotodynamic pump is a kinetic machine in which energy is continuously imparted to the pumped fluid by means of a rotating impeller, propeller, or rotor, in contrast to a positive displacement pump in which a fluid is moved by trapping a fixed amount of fluid and forcing the trapped volume into the pump's discharge. Examples of rotodynamic pumps include adding kinetic energy to a fluid such as by using a centrifugal pump to increase fluid velocity or pressure.

Narec, since 2014 known as the National Renewable Energy Centre, is a part of the Offshore Renewable Energy (ORE) Catapult, a British technology innovation and research centre for offshore wind power, wave energy, tidal energy and low carbon technologies. ORE Catapult's head office is in Glasgow, Scotland. The centre operates multi-purpose offshore renewable energy test and demonstration facilities. It is similar to other centres, such as NREL in the US and National Centre for Renewable Energies (CENER) in Spain. The National Renewable Energy Centre is based in Blyth, Northumberland.

Current meter A device for measuring the flow in a water current

A current meter is oceanographic device for flow measurement by mechanical, tilt, acoustical or electrical means.

Garfield Thomas Water Tunnel

The Garfield Thomas Water Tunnel is the U.S. Navy's principal experimental hydrodynamic research facility and is operated by the Penn State Applied Research Laboratory. The facility was completed and entered operation in 1949. The facility is named after Lieutenant W. Garfield Thomas Jr., a Penn State journalism graduate who was killed in World War II. For a long time, the Garfield Thomas Water Tunnel was the largest circulating water tunnel in the world. It has been declared a historic mechanical engineering landmark by the American Society of Mechanical Engineers.

References