Impact
Hypersonic and high-speed flow research at UNSW Canberra investigates the gas dynamics of chemically reacting and real-gas flows. These inform the design of the hypersonic propulsion systems and planetary entry systems required to achieve practical hypersonic flight for high-speed aircraft. This is achieved by solving fundamental problems in aerothermodynamics, including the effects of chemical reactions and real-gas effects on laminar and turbulent flows of gas mixtures.
These processes include separated flows, leading-edge bluntness effects, surface temperature effects, wake flows, and fluid-thermal-structural interactions. We investigate these processes using a combination of experimental, mathematical analysis, and numerical simulation.
We have several significant research achievements, including:
- The first demonstration of laser ignition as a means of enhancing the supersonic combustion of hydrogen.
- The world’s fastest scanning absorption-based temperature measurements, capable of 1.6 million spectra (and hence temperature measurements) per second.
- Developing instrumented free-flight models for developing hypersonic control parameter databases for generic flight configurations.
- Developing resonantly enhanced shearing interferometry (RESI), a flow visualisation technique for low-density flows that increases sensitivity to density gradients by more than 100 times.
- First measurements of 2D two-component velocity distributions in hypersonic separated flows using a non-intrusive technique, resulting in advances in analytical modelling of these flows.
- Developing new non-intrusive technologies for measuring fundamental quantities such as diffusion coefficient and viscosity at rarefied conditions, where such measurements have previously proved too difficult to perform.
- We host a database of our own high-speed FSI unit cases and those of the international community. View the high-speed FSI unit cases.
Competitive Advantage
We invested several decades to understanding the application of advanced laser-based diagnostic techniques to hypersonic flow measurements.
- We have one of very few facilities in the world with a suite of several non-intrusive measurement and visualisation techniques with the ability to generate conditions simulating high-speed flight. This makes our facility among the best understood and best characterised hypersonic facilities in the world.
- We also have other facilities including a supersonic wind tunnel for steady supersonic flows with Mach numbers 2 to 3, or a rectangular shock tube with a 150 mm x 75 mm cross-section, together with a suite of high-speed cameras (frame rates up to 10 million framers per second) combined with several different visualisation systems (schlieren, shadowgraph, shearing interferometry), which can be used individually or as combinations.
- We are capable of testing models with hot walls, to more realistically simulate real gas conditions of hypersonic entry and flight scenarios.
- Our combination of hypersonic and diagnostic expertise makes us a leading research group in the area of supersonic ignition and combustion processes.
- We have long-standing expertise in the design, simulation, and measurement of the thermal-structural behaviour of high-speed vehicles and propulsion systems.
- We have developed unique capabilities for the dynamic testing of critical aspects of hypersonic flight including:
- fluid-thermal-structural interactions
- the use of tunnel-based free flight testing for the characterisation of the aerodynamic envelope of vehicle geometries and dynamic separations system in the loop testing of control approaches including fluidics.
Successful Applications
- We developed and flight-tested a hypersonic air-speed sensor that was simpler and more robust than previous designs, and survived accelerations over 20g in flight.
- Our patent for a laser-based subsonic airspeed sensor can be used to augment pitot tube measurements but is less susceptible to freezing than pitot tubes.
- Our separated flow velocity measurements are being used to validate state-of-the-art simulations of hypersonic separated flow, a problem that is notoriously difficult to both measure and simulate.
- Data from our instrumented free-flight tests are used to validate aerodynamic databases and inform control models for hypersonic vehicles.
- Our fluid-structural interaction measurements are used by international collaborators to validate their numerical simulations.
- We are currently investigating the effect of shock waves in the water on the tenderness and shelf life of high-value meats, an application showing the cross-disciplinary benefits of investigating high-speed flows.