A COMPACT HIGH PERFORMANCE HEAT EXCHANGER FOR THERMAL MANAGEMENT OF HYPERSONIC AEROSPACE VEHICLES

THERMAL MANAGEMENT SYSTEMS FOR HYPERSONIC AEROSPACE VEHICLES MUST SIMULTANEOUSLY MEET THREE CHALLENGING REQUIREMENTS: (1) HEAT MUST BE REMOVED AT VERY HIGH HEAT FLUXES FROM SURFACES SUCH AS THE COMBUSTION CHAMBER WALL AND AERODYNAMICALLY HEATED SURFACES, (2) THE PROPELLANT MUST BE PREHEATED TO VERY HIGH TEMPERATURES PRIOR TO COMBUSTION, AND (3) THE SYSTEM'S SIZE AND MASS MUST BE HELD TO A MINIMUM. THE PROPOSED EFFORT WILL DEVELOP AN INNOVATIVE HEAT EXCHANGER WHICH MEETS ALL THESE REQUIREMENTS USING SUPERCRITICAL HYDROGEN COOLANT. THE PROPOSED DESIGN ACHIEVES VERY HIGH HEAT FLUXES AT A SIZE AND MASS WHICH ARE MUCH LESS THAN POSSIBLE WITH CONVENTIONAL HEAT EXCHANGER TECHNOLOGY. SYSTEM MASS IS FURTHER REDUCED BECAUSE INTERMEDIATE TWO-PHASE COOLANT LOOPS ARE UNNECESSARY, AND COOLANT PUMPING POWER REQUIREMENTS ARE REDUCED DUE TO THE LOW PRESSURE DROP CHARACTERISTICS OF THE PROPOSED HEAT EXCHANGED. PAYOFFS OF THE PROPOSED EFFORT ARE REDUCED MASS FOR THE INTERNAL THERMAL MANAGEMENT SYSTEM, EFFECTIVE COOLING OF CRITICAL HIGH-HEAT FLUX SURFACES AND EFFICIENT PREHEATING OF PROPELLANT PRIOR TO COMBUSTION.