University of Tasmania, Australia

Unsteady Aerodynamics of Axial Compressors

Air travel represents a significant and growing contributor to greenhouse gas production. Gas turbine engines are widely used for aircraft propulsion and power generation and more efficient designs are required. Unsteady flow inside the engine results from the very nature of the compression process. Air is compressed as it passes through many rows of rotating and stationary blades. Although the pressure rise across each row is small, in a commercial compressor, the combined result of many rows leads to air being compressed to 40 times atmospheric pressure with temperatures reaching 500-600 °C. The relative motion of moving and stationary blade rows causes a range of unsteady flow effects, including the interaction of blade wakes from upstream blades rows with downstream blades rows. This results in fluctuating turbulence levels at the downstream blade rows, which then causes changes in aerodynamic performance. To date engine designers have not taken these effects into account. Any improvement in performance will lead to improved fuel economy and this translates into reduced greenhouse gas emissions. The researcher will join a well regarded research team and have opportunities to collaborate with researchers at Cambridge University, UK, and engine designer Rolls-Royce Plc, UK.

The aim of this research project is to improve axial compressor design through better understanding of unsteady flow effects. This project will involve numerical studies of the unsteady flow on the blade surfaces, including the boundary layer transition processes. Simulated results will be compared with experimental results measured inside a low-speed research compressor.