Assessment of the Impact of an Advanced Power System on a Turboelectric Single-Aisle Concept Aircraft

Electrified aircraft propulsion concepts show potential in using propulsion airframe integration to decrease fuel burn and emissions. Even though electrification offers component efficiency values greater than 90 percent, at high power levels this results in the generation of significant amounts low grade waste heat. A major challenge of electrified aircraft propulsion is managing that heat while minimizing any penalties associated with a thermal management system. This paper explores the potential benefit of power distribution and thermal management innovations at the aircraft system level demonstrated on a turboelectric single-aisle concept. The first innovation is high-efficiency components that eliminate over half of the waste heat. The second takes advantage of the outer mold line of the aircraft to reject heat directly to the environment passively, instead of adding active cooling loops that negatively impact the weight, power, and drag of the aircraft. In order to fully grasp the impact of the advanced power system, we develop methods of modeling the power and thermal management systems to be integrated in the full aircraft conceptual model. In our first model, which acts as a baseline for our study, the aircraft is designed with a state of the art DC power system and active cooling loops. Our second model includes an advanced power system with active cooling, which results in a fuel burn reduction of 2.5 percent. Finally, in our third model, we assess the benefit of an outer mold line cooling scheme with the advanced power system. The outer mold line cooling scheme with an advanced power system yields an additional 0.8 percent reduction in fuel burn, for an overall fuel burn reduction potential of 3.3 percent in addition to aerodynamic benefits from propulsion airframe integration enabled by electrified aircraft propulsion.