Evaluation of Dual-Mode Combustor Characteristics with Vitiated and non-Vitiated Inflow

Abstract

Supersonic combustion tests were conducted with a direct connected dual-mode combustor. To generate high enthalpy flow, either a hydrogen fueled vitiation heater or a storage heater was used to compare the inflow vitiation effects on the combustor wall pressure distributions. Regarding the storage heated flow, two stagnation temperature conditions were tested. One had a same level stagnation temperature to the vitiated flow, and the other was a higher stagnation temperature which was estimated to gives a matching pressure increase between vitiated and clean air flow. The experimental results showed that the pressure increase ratio of this higher stagnation temperature condition with clean flow seemed to give slightly smaller pressure magnitudes compared to the vitiated flow case at same equivalence ratio. In addition, OH radical gave small effects on pressure distributions. NomenclatureJ/kg H = ramp injector height, H = 6.35mm M = Mach number MW = Molecular weight P = pressure Ru = Universal gas constant T = temperature VAH = Vitiation Air Heater SAH = Storage Air Heater γ = specific heat ratio φ = Fuel equivalence ratio dq = Fuel heat release value, J/kg * = throat condition 0 = stagnation condition air = condition of air flow fuel = condition of fuel flow w = condition on wall