Injector-Integrated Fuel-Air Heat Exchanger Module

Modern high efficiency gas turbine engines typically operate with hot section temperatures so high that metal parts in those areas need to be cooled to maintain strength and life properties. A well-established approach to this bleeds a portion of the compressor discharge air to flow through and over turbine parts. As engine compressor pressure ratios continue to increase, the temperature of this compressor discharge air also increases, to the point that the cooling air itself needs to be cooled. Micro Cooling Concepts is involved in developing a concept for a heat exchanger co-located/integrated near the point of fuel injection in order to provide cooled cooling air. The main advantages of this concept are the minimization of the amount of heated fuel between the heat exchanger and fuel injector tip such that the fire danger from leaking tubing is eliminated, and the ease of delivering cooled cooling air to the secondary air circuit. Additionally, the modular concept distributes the heat exchange function, allowing for easy replacement of an individual heat exchanger module. For this program, high temperature materials will be used for fabrication using Micro Cooling Concepts' laminated foil construction approach. This effort supports the NASA goal of improving aeropropulsive efficiency through reduced fuel burn and increased cycle temperatures, specifically by enabling very high turbine cooling effectiveness.