Propellers with Integrated Thermal Management for Electrified Aircraft

Electrified aircraft offer advantages in operating cost amp; maintenance, energy economy, noise, and emissions, and with the increased heat dissipation demands due to modern avionics, thermal management is more critical than ever. Fuel has been the traditional heat sink for aircraft, but its heat sink capacity has been stressed by increased heat dissipation loads. For electrified aircraft, this heat sink may not exist, or may not be accessible where waste heat is generated. Therefore, alternate heat sink concepts using ambient air have been considered, including liquid cooling on the outer mold line (OML) or via heat exchangers with ducted air. Direct OML cooling is preferred, as it does not add drag, but OML cooling complicates the thermal sizing, since its performance is dependent on location, speed, altitude, and angle-of-attack. This is tractable, but the biggest issue lies with the mismatch between heat load and cooling performance. Thus, it would be desirable to augment the heat dissipation capacity at takeoff. One means of accomplishing this is to make use of the propellers/propulsors on the aircraft, which are adjacent to a major heat source: the electric motors. Their distribution also provides cooling access at multiple points on the aircraft, reducing the need to transport waste heat or cooling fluids. Micro Cooling Concepts has a history in creating ultra-thin high-performance heat transfer structures and will leverage this experience to develop blade-integrated cooling concepts that are constructed of aluminum or titanium alloys.nbsp;The program will consist of integrated cooling design studies, cooling loop interface development, and prototype test article fabrication and characterization in support of the development of a frac14;-scale prototype of the SUSAN aircraft concept. This effort supports the NASA goal ofnbsp;reducing the mass and increasing the efficiency of heat acquisition and rejection componentsnbsp;and advancing technologies for more electric aircraft.