Development of a 3D Sizing Model for All-Superconducting Machines for Turbo-Electric Aircraft Propulsion

Distributed propulsion in aircraft brings many advantages in terms of efficiency and noise reduction. While the distribution can be done mechanically through the use of gears and transmissions, electrical propulsion allows for lower maintenance needs, higher efficiency, and lower emissions through the complete decoupling of the gas turbines and the propulsion fans. Such systems have been investigated in the past and NASA is executing on a development plan to bring turbo-electric propulsion systems for transportation aircraft by 2035. The very high specific power required for the airborne generators and motors can only be achieved by using superconductors. Analytical 2-D sizing models have been created and showed very promising results. NASA is now funding the development of higher fidelity models for superconducting machines in which an actual 3-D representation of the geometry is considered. The magnetic flux distribution is calculated using Biot-Savart's law coupled with the magnetic moment method for the backiron. The code also includes thermal and mechanical models allowing for a full and accurate design. The paper describes the model architecture and the methods used to perform high-temperature superconducting machine sizing and optimization.