The bladeless turbine, a clean expansion device for rotating detonation combustors
Purdue University
Abstract
In the past decade, pressure gain combustion research has promised over ten percentage-points of increase in power plant thermal efficiency. The impact of a mere two percent increase in fuel efficiency for airplane engines would save over one billion dollars for the United States per year, not to mention potential reductions in size, weight, complexity, and cost of engines. However, to realize such potential gains, the turbine must be effectively coupled with the rotating detonation combustor (RDC), whose exhaust conditions differ substantially from current state of the art turbines. The RDC utilizes isochoric combustion through detonation waves traveling at supersonic speeds, and is suitable for many types of fuels, especially carbon-free fuels such as hydrogen. We will first go over the characterization of rotating detonation combustors (RDCs). Afterwards a new type of turbine, the wavy-shaped bladeless turbine is introduced. This is an energy conversion unit for the combined power extraction and thrust increase which can be employed in high subsonic to hypersonic flows, and especially suitable for RDCs. The seminar will include the advantages and current state of bladeless turbines, the design procedure, the performance characteristics, and an experimental validation in a supersonic wind tunnel through high-frequency probe-based and optical measurements.
About the speaker
Dr. James Braun graduated from the KU Leuven (Belgium) as mechanical engineer. He performed a research master’s degree at the von Karman institute for fluid dynamics (Belgium) in 2015 within the Aerospace and Aeronautics department. His thesis was on the ‘Characterization of complex multi-physics flow in rotating detonation engines’ for which he won the Prince Alexandre of Belgium Award for the Best Presentation. He obtained his PhD from Purdue University (USA) in 2019 entitled ‘power harvesting from shock waves: the axial bladeless turbine’. In 2018, he was awarded with the AIAA Gordon C Oates Air Breathing propulsion graduate award. He was an ORISE postdoctoral researcher in 2019 and is currently a research assistant professor at Purdue University within the PETAL group (Purdue Experimental Turbine Aerothermal Lab).
