Fuel Injection into a Supersonic Airflow by Means of Pylons

Abstract

The mixing and reaction processes in a scramjet combustion chamber have been experimentally investigated. Hydrogen was injected into a preheatedMach 2.15 airstream by means of pylon-like fuel injectors. The supersonic  ame was stabilized in a purely reaction–kinetical way; i.e., by means of self-ignition. Various pylon designs have been employed to study their in uence 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  ow, nonintrusive, optical measurement techniques have been employed: the Rayleigh scattering technique to study the injected mixing jets, and the self- uorescence of the OH radical to determine location and intensity of the reaction zones. Additionally, the wall static pressure has been measured.