The rotating detonation engine (RDE) or continuous detonation wave engine is acknowledged by many to be among the most promising pressure gain combustion technology approaches. While initially demonstrated in the 1960s, the highly transient operation, particularly relative to the injection system, has made it difficult to optimize performance. However, recent advances in high-speed data acquisition (including optical and laser-based measurements), combined with vastly improved computational tools, provide an environment suitable to rapidly advance the technology. The project team at Purdue University – along with industry consultant input from United Technologies Research Center (UTRC) – will conduct detailed measurements in both an operating RDE and a simplified system that will quantify key physics important for the design and optimization of RDEs, specifically, in the areas of fuel/air mixing, unsteady injector operation, and turbine integration characterization. The technical approach includes experimental studies (using an optically-accessible injection dynamics facility and a subscale combustor facility) as well as computational fluid dynamics (CFD) modeling analyses. The project team will ultimately work to develop a method to quantify net pressure gain in an operating RDE.