Design and Analysis of the Thermal Management System of a Hybrid Turboelectric Regional Jet for the NASA ULI

Presented at AIAA/IEEE Electric Aircraft Technologies Symposium 2020A team of researchers from multiple universities are collaborating on the demonstration of a hybrid turboelectric regional jet for 2030 under the NASA ULI Program. The thermal management is one of the major challenges for the development of such an electric propulsion concept. Existing studies hardly modeled the thermal management systems with the propulsion systems nor integrated it to the aircraft for system- and mission-level analyses. Therefore, it is very difficult to verify whether a design of the thermal management system is feasible and optimal based on current literature. To fill this gap, this paper presents a design of the thermal management system for the hybrid turboelectric regional jet under the ULI program and integrates it to the aircraft. The TMS is tested against the cooling requirements, where the thermal loads from the electric propulsion system are quantified through the whole mission. Potential solutions for peak thermal loads during takeoff and climb are also proposed and analyzed, where additional coolant or phase change materials are used. Moreover, the impacts of the TMS on the system- and mission-level performance are investigated by the presented integration approach as well. It is discovered that a basic oil-air thermal management system cannot fully remove the heat during the early mission segments. Using additional coolant or phase change materials as heat absorption can handle such heating problem, but penalty due to additional weight is added. It is found that greater penalties in fuel burn and takeoff weight are added by additional coolant solution than the phase change material solution.NASA, GR1000571

An Update on Sizing and Performance Analysis of a Hybrid Turboelectric Regional Jet for the NASA ULI Program

Presented at AIAA/IEEE Electric Aircraft Technologies Symposium 2020Under the NASA University Leadership Initiative (ULI) program, a team of universities are collaborating on the advancement of technologies a hybrid turboelectric regional jet, with an intent to enter service in the 2030 timeframe. In the previous studies of the ULI program, the in-service benefits of the technologies under development were analyzed by integrating the technologies of interest to a 2030 regional jet with a hybrid turbo-electric distributed propulsion system. As the program has progressed, the projected performances for each technology and subsystem have been updated. This paper presents an update in the sizing and performance analysis of the regional jet with the hybrid turbo-electric distributed propulsion system, by integrating the updated values of the technologies and subsystems to the vehicle. The updates in this paper include the DC/AC conversion links, efficiency of generator and cabling losses, weight of the wires, the battery cooling through the environmental control system, motor and inverter cooling by the thermal management system, and the redundancy strategy of the propulsion system. The updates of the results from the integrated model include the overall efficiency of the propulsion system, mission fuel savings, mission energy flow distribution, and the optimal hybridization rate in climb and cruise. The overall fuel saving benefit for the target 600-nmi mission is 19.9% compared to the baseline aircraft.NASA, GR1000571

Environmental Design Space Assessment of Continuous Lower Energy Emissions and Noise (CLEEN) Technologies

09-C-NE-GIT-001, Amendment Nos. 002The Partnership for AiR Transportation Noise and Emissions Reduction \u2014 PARTNER \u2014is a cooperative aviation research organization, and an FAA/NASA/Transport Canada sponsoredCenter of Excellence.The Federal Aviation Administration (FAA) is pursuing the development of Continuous Lower Energy, Emissions and Noise (CLEEN) technologies for civil subsonic jet airplanes to help achieve the Next Generation Air Transportation System (NextGen) goals. These goals are to reduce significant community noise and air quality emissions impacts in absolute terms and limit the impact of aircraft CO\u2082 emissions on the global climate by achieving carbon neutral growth by 2020 compared to 2005, thereby allowing sustained aviation growth. The objectives of this project leverage the research conducted under the Environmental Design Space (EDS) development program (PARTNER Project 14) and the National Aeronautics and Space Administration (NASA), to use EDS to independently model and assess the benefits of the technologies being developed under the CLEEN Program. EDS has been jointly developed by NASA and FAA and has been used to assess a wide variety of both conventional and advanced technology configurations. The project focused on six primary elements: (1) public domain aircraft technology modeling (Phase I); (2) proprietary CLEEN aircraft technology modeling (Phase II); (3) vehicle level assessments of fuel burn, noise, and NOx incorporating these technologies; (4) fleet-level assessments of fuel burn and NOx using vehicles with these technologies; (5) development of an Excel-based technology dashboard for use at the FAA; and (6) examining historical trends in aircraft technology. The most significant outcome of this work was vehicle and fleet-level benefit assessments of the CLEEN aircraft technologies with regards to fuel burn, NOx emissions, and noise. Additionally, the Excel-based dashboard that was developed provides FAA with an in-house capability beyond the conclusion of this project to quickly assess combinations of these technologies and their benefits