Some Design Aspects of A Strut-Based Hydrogen Fueled Scramjet Combustor

Hypersonic flight with air-breathing propulsion is given due importance for its potential to have cost-effective access to space and high-speed cruise. Hypersonic air-breathing propulsion is based on scramjets and ramjets, the simplest jet engines to propel a vehicle to hypersonic speeds within the atmosphere. The specific thrust of a scramjet engine exceeds that of other propulsion systems [1, 4]. Nations around the globe have shown keen interest in mastering this technology. ISRO has also been able to successfully flight test this technology. One of the key aspects is the way in which fuel is introduced into the supersonic free-stream. Various methods like cavity based fuel injection and strut based fuel injection are tried and tested. In the study, for a strut based system with gaseous hydrogen as fuel the effect of flare and expansion angle on fuel-air mixing and subsequently the overall combustion efficiency of the system is looked into.