Successful Scramjet Combustor Testing Published Dec. 12, 2006 By Plans and Programs Directorate AFRL/XP WRIGHT-PATTERSON AIR FORCE BASE, Ohio -- AFRL's Robust Scramjet [supersonic combustion ramjet] program establishes new and improved capability in dual-mode scramjet combustors along three major pillars: scalability, operability, and durability. Working under the Robust Scramjet program, Aerojet (Orange, Virginia) successfully completed the initial test series on a missile-scale round scramjet combustor. Round combustor geometries are favorable due to their ability to withstand internal pressure. Eliminating the inherent corner effects of two-dimensional geometries reduces both the surface area and the overall weight of the combustor. Engineers conducted the tests at enthalpies typical for Mach 2.7 to Mach 5 flight. The tests demonstrated the use of technologies for increasing the operability of scramjet engines over the current baseline. They also established a baseline dataset to support the structurally efficient round combustor's scalability for engines suitable for cruiser aircraft and space applications. The engineers employed a variety of fuel injector arrangements, fueling levels, and other test conditions. They collected data related to thrust, combustor pressures and temperatures, and flow. The results of their analysis exceed the goals set forth by the Air Force for improved dual-mode scramjet engines. AFRL engineers provided Aerojet with technical support, test article design, computational flow modeling, and data analysis support. These tests will help pave the way for the development of larger combustors