Rotating Detonation Engine Operation

Abstract

A Rotating Detonation Engine engineered and manufactured by Pratt and Whitney Seattle Aerosciences Center was loaned to the Air Force Research Laboratory at WrightPatterson Air Force Base for further testing and development. The engine was originally designed for ethylene and oxygen, but was altered in order to use hydrogen and air. The engine was tested at a wide range of flow rates and equivalence ratios with hydrogen-air in order to obtain a matrix of the operating space. Although a considerable portion of the test matrix contained successful detonations, all of the detonations that occurred for the tested configuration were in the fuel rich operating regime. In the pursuit of greater thrust output and a wider range of operability, the air was slightly enriched with additional oxygen. The addition of extra oxygen not only increased the range of thrust output and operability, it also allowed the engine to detonate at high enough air mass flows that two detonation waves were established in the engine. The detonation wave activity during the approach and through the transition from one detonation wave to two detonation waves was analyzed in order to gain a deeper understanding of the transition phenomenon.