Advanced Designs for Main and Oxidizer Rich Pre-Burner Injectors Utilizing Mixing Biasing for Reusable LOX/Hydrocarbon Engines

To meet IHPRPT goals for LOX/HC booster engines, improvements must be made in performance, thrust/weight, life, reliability, and cost. To date, operational LOX/hydrocarbon engines have used the fuel as the thrust chamber assembly (TCA) regenerativecoolant, and have used fuel film cooling (FFC) as the TCA hot gas wall protective layer. The present hydrocarbon fuels show increasing coking behavior at high chamber pressures (Pc) and heat loads, thus limiting their utility for long-life reliablesystems. The Russians have successfully implemented fuel dump cooling, but with significant performance loss. In addition, some of the most attractive Advanced Hydrocarbon (AHC) fuels may not be suitable for TCA cooling due to limited thermal capacity ormonopropellant tendencies. Schafer proposes an analytical and experimental single and multi-element injector program to investigate the potential for FFC and oxidizer film cooling (OFC) with implementation of Mixing Biasing in the outer ring in order toimprove performance and reduce heat flux. The net result will be the development of design database summarizing ERE and chamber heat flux for each configuration investigated. The proposed program will support the full-scale development of a high Pc LOX/HCengine adaptable to AHCs and satisfying Phase II IHPRPT goals. The development of this technology will enable the full-scale development of a high Pc LOX/HC engine adaptable to AHCs and satisfying Phase II IHPRPT performance goals and NASA requirements.The technology is applicable to Air Force Hydrocarbon Boost program goals and can be adapted to commercial or government RLV and expendable launch vehicles.