Session: 01-12 Electrified Propulsion and Novel Cycles II

Paper Number: 153111

Mapping the Potential of Hybrid Electric Architectures for Commuter Aircraft 

The aviation industry faces significant environmental challenges, driving a well-established set of strict regulations aimed at reducing the need for carbon-based energy and associated emissions. While flight electrification is one of the potential routes, limitations in battery technology are forcing designers and manufacturers to focus their efforts on the commuter and regional class. Although this type of aircraft contributes less to global aviation emissions, it serves as a crucial stepping stone for the adoption of electrified propulsion systems in larger aircraft. Nevertheless, community opinions remain divided regarding which electrification approach is most beneficial and which system-level design factors drive the variant selection. This work aims to provide a systematic breakdown and comparison of different hybrid electric variants in order to quantify their potential, enabling technology goals, design drivers and shortcomings.

A multi-disciplinary framework is utilized, comprising modelling approaches for multi-point thermal engine design, physics-based electrical component sizing and performance, aircraft sizing, mission design, and environmental assessment. Several battery-powered hybrid electric architectures are generated and compared to assess their performance features and environmental potential. A baseline kerosine-fueled conventional configuration acts as the reference point. A parallel hybrid, series hybrid, turboelectric, and series/parallel partial hybrid electric architecture are the variants under investigation. All configurations utilize propellers for propulsion, driven either by the thermal, electrical powerplant, or their combination. The two latter concepts also introduce a boundary layer ingestion fan, which is mounted in the aft of the aircraft and powered by an electrical motor. A battery system acts as the electrical energy source, while kerosine-fueled turboshaft engines comprise the thermal powerplant. The electrified architectures are investigated within the scope of commuter and regional flight.

For each electrification concept, a breakdown of subsystem impact on the overall integrated engine-aircraft design and performance is conducted. The contribution of propulsor performance and size, power system and energy source design, mass and efficiency are highlighted to quantify the impact, sensitivity and importance of each discipline that comprises a hybrid electric aircraft. Following this, an exploration of the range capability of each configuration with respect to the projected advancements in electrical power system technology, is performed to reveal the optimal hybridization of each concept. At the same time, the limitations and potential of each concept are analysed, along with the electrification scheme that best meets them.

In conclusion, a developed integrated framework for the design of hybrid electric propulsion systems and aircraft configurations is deployed in to assess the most promising electrified versions of the commuter and regional aircraft class. A systematic subsystem impact breakdown highlights the significance of the added electrical power system mass and correlates it with the expected electrification benefit accrued from lesser fuel consumption and potentially more efficient powertrains. The investigation of range capability with respect to electrical system technology goals, demonstrates the concept of operation and degree of electrification that the hybrid electric aircraft designer should aim for to achieve optimal environmental performance and certification compliance.

Presenting Author: Dimitrios Bermperis Malardalen University

Presenting Author Biography: Dimitrios Bermperis is currently a Ph.D. candidate in Energy Engineering at Mälardalen University (MDU) in Västerås, Sweden. He holds a Diploma of Mechanical Engineering from the Aristotle University of Thessaloniki, Greece. His current research focuses on hybrid-electric and hydrogen-fired propulsion system configurations for regional aircraft. The work is directed towards the conceptual design, performance and integration with the turbine engine and aircraft.

Authors:

Dimitrios Bermperis Malardalen University
Mavroudis Kavvalos German Aerospace Center (DLR)
Stavros Vouros Mälardalen University
Konstantinos G. Kyprianidis Mälardalen University