Thermofluids lab
The Thermofluids experimental facilities in Durham consist of two large laboratories, with a total of twelve separate wind tunnels. Both labs are mixed teaching and research labs so students can see innovative research in action. The main facilities are detailed on this page.
The Durham 2 metre Tunnel
The wind tunnel was designed and built entirely within the School.
Specification
- Maximum model size: 40% full scale (passenger or racing cars)
- Open jet (minimises model blockage effects).
- Open return (maximises working section dimensions within the available space)
- Twin centrifugal fans located downstream from the working section.
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Long working section to allow slipstreaming studies
Features include
- 3 and 6-componment force balances available with computer data system.
- Computer controlled supporting strut with height and pitch control.
- Laser ride height sensing at two positions.
- 3-D PIV System with computer controlled traverse system.
- Multi-axis probe traversing system.
- Scanivalve pressure sensing system (up to 144 channels).
- Fast response pressure transducer bank for transient studies.
- Wheel surface pressure telemetry system.
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Moving ground plane.
The Durham Cascade
The primary tool over many years at Durham for Secondary Flow research has been the so-called Durham Cascade. This will known test rig is a low speed, large scale linear cascade of six rotor blades taken from a high pressure rotor design. The cascade has been a popular computational test case and is one of the most computed pieces of experimental equipment in the world - largely due to the fact that although the geometry is easy to set up the flow is highly complex.
The Cascade has recently undergone a major refurbishment which allows us to test complex 3D geometries used in the latest aero-engines such as those that power the Airbus A380.
Specification
- Model size: 8x full scale blade
- Typical blade size: 191mm pitch, 375mm span, 181mm chord
- Eight passages
- Inlet turbulence level 5%
- Inlet velocity 20m/s
Features include
- 4 axis computer controlled traversing gear
- Cartridge design allows arbitary blade profiles to be tested
- Five hole pnematic probes gives complete flow field information including loss
- Sterolithography pressure tapped blades
- Large Scale allows detailed flow visualisation studies in oil and dye
Oscillating compressor cascade
This cascade, provides detailed exerimental measurements to validate complex CFD codes developed at Durham. It's unique feature is that it features an oscillating blade and instrumentation designed to capture the effects that this oscillating blade has on other blades in the cascade.
Specification
- Typical blade size: Span 0.2m; Chord: 0.15m, Pitch 0.1m
- Number of blades: 7
- Inlet velocity: 10-30m/s
- Frequency of oscillation: 5-30Hz (mechanically driven).
- Incidence range: +10deg to -10deg
- Mass flow: 3-5 kg/s
- Instrumentation: Sensym pressure transducers linked to data logger
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Capable of measuring raw and ensemble-averaged unsteady pressures; 5 hole probe traversing, flow visualisation, etc.
Stirling engines
Small Stirling engines are at present being used commercially for Micro Combined Heat and Power (MCHP) applications. The School has a laboratory prototype of a MCHP unit equipped with a PC data acquisition system and a comprehensive instrumentation suite.
This unit is also used to determine the heat balance of the device and to provide experimental validation of thermodynamic and computational fluid dynamics (CFD) models of engines and burners. CFD modelling is applied to more accurately define the geometry and dimensions of high performance MCHPs.
The lab currently holds two major Stirling engine test rigs:
Laboratory prototype of a Stirling engine MCHP system
Specification
- Electrical Output: 0.5 kWe
- Thermal Output: 8 kWth
- Fuel: natural gas
- Working fluid: Helium
- Maximum pressure: 70 bar
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Speed: 1500 rpm
A test rig with a WHISPERGEN Mk III MCHP unit
Specification
- Electrical Output: 1 kWe
- Thermal Output: 6 kWth
- Fuel: natural gas
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Working fluid: Nitrogen
Teaching rigs
A large number of teaching rigs are available which give undergraduates 'hands on' experience, some of the highlights include:
- A computer controlled 1.9 Litre Volkswagen diesel engine test bed
- A transonic flow tunnel featuring Schlieren Optical System incorporating TV capture of shockwaves
- A 3 m pipe flow experiment to demonstrate laminar and turbulent flow
- A hydraulic pump experiment featuring visualisation of cavitating flow
