An industrial point of view on scramjet combustor design

Abstract

AEROSPATIALE Bourges, in connection with AEROSPATIALE Les Gâtines for the CFD support, carries on with the development of his knowledge in airbreathing propulsion (especially ramjet) up to the hypersonic speed. This work includes air intakes, scramjet facilities, scramjet combustor, new measurement techniques (in the scope of PREPHA program), others cycles (precooled air, Pulsed Detonation Wave Engine, …), new test facilities (such as the Adiabatic Compression Wind Tunnel and flying test facilities).

AEROSPATIALE is especially a great actor in the PREPHA program, which is devoted to research about supersonic combustion and hydrogen-fueled scramjet technology. In this scope, AEROSPATIALE designed and built a scramjet model called “CHAMOIS” (French acronym for Modular CHAmber for Optimization of Scramjet Injection). This combustor of an attractive size (0,05 m2 entrance area) is equipped with wall measurement systems and optical means : this allows french specialists to estimate the combustor efficiency, to compare different shapes and injection systems, to understand the real size scramjet phenomena and to validate the numerical tools. The nominal conditions of tests correspond to a flight at Mach 6.

CHAMOIS scramjet has been tested successfully in Bourges, tests are going on.

Concerning the measurement techniques, AEROSPATIALE is trying to breach the wall between the industrial use (pressure taps, thermocoples, …) and the laboratory techniques (unsteady maps by optical means …), by selection of near-term methods to be tested in scramjet test benches in Bourges.

Flow field combustor design parameters have been estimated by analytical codes, 2D and 3D reactive Navier-Stokes computations have been performed, especially to help to understand the phenomena.