Fuel injection into a supersonic airflow by means of pylons

The mixing and reaction processes in a scramjet combustion chamber have been experimentally investigated. Hydrogen was injected into a preheated Mach 2.15 airstream by means of pylon like fuel injectors. The supersonic flame was stabilized in a purely reaction-kinetical way; i.e., by means of self-ignition. Various pylon designs have been employed to study their influence on fuel mixing and combustion in the supersonic airstream, Based on the results, an optimized fuel injector has been designed and tested. To assess the reacting flow, nonintrusive, optical measurement techniques have been employed: the Rayleigh scattering technique to study the injected mixing jets, and the self-fluorescence of the OH radical to determine location and intensity of the reaction zones. Additionally, the wall static pressure has been measured.