High Heat Flux Facility Design for Testing of Advanced Hydrocarbon Fuel Thermal Stability

摘要

The Air Force Research Laboratory's Propulsion Directorate is developing higher energy density hydrocarbon fuels for application in reusable liquid rocket engines. For increased performance and operability, next generation engines will require better thermal stability understanding of hydrocarbon fuels under high heat fluxes. Of the existing thermal stability test rigs, none have the ability to accurately simulate the high heat flux conditions that will exist in the cooling channels of these new high-pressure hydrocarbon engines. To design and test fuels to meet the high reliability and reusability requirements proposed for these engines, the Air Force Research Laboratory (AFRL) at Edwards AFB has designed the High Heat Flux Facility (HHFF) using experience gained from past thermal stability test rig experiments. In order to design a facility capable of simulating the higher heat fluxes expected in the channels, CFD++, a Metacomp Technologies Inc. computational fluid dynamics software suite, was employed to optimize the design prior to manufacture. Conjugate heat transfer calculations were performed in a single computational domain containing the copper heater block and the fluid channel of the new test rig design. The parameters of interest during each experiment will be heat transfer coefficient, degree of coking and corrosion in the channel, and pressure drop as a function of heat flux, wall temperature, Reynolds number, channel material, fuel composition and pressure. AFRL's HHFF will be an important tool for facilitating the development and transition of new advanced hydrocarbon fuels.