HIGH PERFORMANCE AIRCRAFT SURFACE HEAT TRANSFER TECHNOLOGY

A NEW APPROACH TO HIGH EFFICIENCY HEAT EXCHANGER DESIGN SHOWS THAT THEORETICAL LIMITS TO SPECIFIC CONDUCTANCE ARE ABOUT 100,000 TIMES GREATER THAN IS CURRENTLY ACHIEVED IN MOST STATE-OF-THE-ART COMPACT EXCHANGERS, BUT PRACTICAL CONSIDERATIONS REDUCE THIS FACTOR TO PERHAPS 100. PROTOTYPE MICRO-TUBE STRIP (MTS) HIGH PRESSURE HE-HE EXCHANGERS HAVE DEMONSTRATED SPECIFIC CONDUCTANCE GREATER THAN 350W/KGK AT FLOW VELOCITIES BELOW 1% OR THE SPEED OF SOUND. THIS MTS EXCHANGER CAN BE ADVANTAGEOUSLY ADAPTED TO GENERAL THERMAL MANAGEMENT AT ULTRA-HIGH POWER-DISTANCE PRODUCTS, FOR COOLING OF HOT AIRCRAFT SURFACES AT HEAT FLUX DENSITIES UP TO 20MW/M(2), ELECTRONIC POWER COMPONENTRY, AND BOUNDARY LAYER FLOW ENHANCEMENT. IT ALSO OPENS MANY NEW AVENUES FOR UTILIZATION OF WASTE HEAT BY GREATLY INCREASING THE ABILITY TO EFFECTIVELY USE REMOTE SURFACE FOR HEAT RADIATION. THE MTS TECHNOLOGY IS EXPECTED TO ULTIMATELY PROVE ECONOMICAL FOR MANY TERRESTRIAL MOBILE APPLICATIONS. IMPLEMENTATION DEPENDS PRIMARILY ON PROGRESS IN SEVERAL NEW MANUFACTURING TECHNOLOGIES INCLUDING SUPERPRECISION PROGRESSIVE FINEBLANKING, HIGH SPEED DIFFUSION WELDING, AND HIGH SPEED PRECISION ROBOTICS.