Hybrid-electric propulsion integration in unmanned aircraft

AIAA Scitech 2019 Forum, 2019

2020

This paper addresses the topic of multidisciplinary analysis (MDA) applied to hybrid electric aircraft (HEA) design focusing on the analysis of multi-fidelity models for hybrid electric powertrain design. The motivation behind this work is the retrofit of a turboprop aircraft with hybrid electric propulsion system. An adapted MDA for multi-fidelity conceptual aircraft design is set in place for the evaluation of the aircraft performance with a hybrid electric propulsion architecture. For the gas turbine system, high fidelity data have been used to develop multi-fidelity models with different levels of detail and complexity. These models have been integrated into the MDA to evaluate the performance of the vehicle for a given mission. Fuel consumption is the main metric used to assess the aircraft performance in the presence of uncertainty introduced on each propulsion model.

2018 AEIT International Annual Conference, 2018

In the last years considerable efforts towards the development of more electric transportation systems have been done. This trend heavily involves also the aerospace industry both civil and military, as demonstrated by numerous research project based on the concept known as More Electric Aircraft (MEA). MEA is based on the utilization of electric power to drive an increasing number of aircraft subsystems; its main goal is the replacement of those systems or actuators powered by hydraulic and pneumatic energy sources with electric drives. Among the main advantages of more electric architectures, it's worth reminding the reduction of the environmental impact and the improvement of the overall performances, with a special attention to the on-board energy management. The latter aspect encompasses all the features of on-board energy provision, storage, distribution and consumption and requires a system level perspective. In the general framework of the More Electric Aircraft concept, this work reports a case of study related to the development of an aeronautical hybrid propulsion system for an Unmanned Air Vehicle (UAV) able to optimize the performance of the aircraft energy management. A laboratory demonstrator of the proposed hybrid architecture was built and tested.

Energies, 2018

Ambitious targets to reduce emissions caused by aviation in the light of an expected ongoing rise of the air transport demand in the future drive the research of propulsion systems with lower CO 2 emissions. Regional hybrid electric aircraft (HEA) powered by conventional gas turbines and battery powered electric motors are investigated to test hybrid propulsion operation strategies. Especially the role of the battery within environmentally friendly concepts with significantly reduced carbon footprint is analyzed. Thus, a new simulation approach for HEA is introduced. The main findings underline the importance of choosing the right power-to-energy-ratio of a battery according to the flight mission. The gravimetric energy and power density of the electric storages determine the technologically feasibility of hybrid concepts. Cost competitive HEA configurations are found, but do not promise the targeted CO 2 emission savings, when the well-to-wheel system is regarded with its actual costs. Sensitivity studies are used to determine external levers that favor the profitability of HEA.

Asia-Pacific International Symposium on Aerospace Technology , 2018

A hybrid-electric propulsion system combines the advantages of fuel-based systems and battery powered systems and offers new design freedom. To take full advantage of this technology, aircraft designers must be aware of its key differences, compared to conventional, carbon-fuel based, propulsion systems. This paper gives an overview of the challenges and potential benefits associated with the design of aircraft that use hybrid-electric propulsion systems. It offers an introduction of the most popular hybrid-electric propulsion architectures and critically assess them against the conventional and fully electric propulsion configurations. The effects on operational aspects and design aspects are covered. Special consideration is given to the application of hybrid-electric propulsion technology to both unmanned and vertical takeoff and landing aircraft. The authors conclude that electric propulsion technology has the potential to revolutionize aircraft design. However, new and innovative methods must be researched, to realize the full benefit of the technology.

Mechanics & Industry

The aviation world is dealing with the development of new and greener aviation. The need for reducing greenhouse gas emission as well as the noise is a critical requirement for the aviation of the future. The aviation world is struggling with it, and a compelling alternative can be the electric propulsion. This work aims to present THEA-CODE, a tool for the conceptual design of hybrid-electric aircraft. The tool evaluates the potential benefits of the electric propulsion in terms of fuel burnt and direct and indirect CO2 emissions. THEA-CODE is suitable not only for conventional “wing-tube” configurations but also for unconventional ones, such as the box-wing. The results show a significant reduction of fuel burnt adopting batteries with energy density higher than the current state of the art. A procedure to find the potential best compromise configurations is presented as well.

Journal of Control, Automation and Electrical Systems, 2021

The present work is a survey on aircraft hybrid electric propulsion (HEP) that aims to present state-of-the-art technologies and future tendencies in the following areas: air transport market, hybrid demonstrators, HEP topologies applications, aircraft design, electrical systems for aircraft, energy storage, aircraft internal combustion engines, and management and control strategies. Several changes on aircraft propulsion will occur in the next 30 years, following the aircraft market demand and environmental regulations. Two commercial areas are in evolution, electrical urban air mobility (UAM) and hybrid-electric regional aircraft. The first one is expected to come into service in the next 10 years with small devices. The last one will gradually come into service, starting with small aircraft according to developments in energy storage, fuel cells, aircraft design and hybrid architectures integration. All-electric architecture seems to be more adapted to UAM. Turbo-electric hybrid architecture combined with distributed propulsion and boundary layer ingestion seems to have more success for regional aircraft, attaining environmental goals for 2030 and 2050. Computational models supported by powerful simulation tools will be a key to support research and aircraft HEP design in the coming years. Brazilian research in these challenging areas is in the beginning, and a multidisciplinary collaboration will be critical for success in the next few years.

Advances in Transdisciplinary Engineering

The article presents the conceptual design of Hybrid Energy Source System (HESS) for Long Endurance Electric UAV. During the design, the MBD method was used to analyze energy consumption during various UAV operational states as well as the entire mission for different HESS concepts. Such analysis at an early stage of the concept allows you to choose the optimal HESS set for a given UAV and expected mission parameters. The design method is based on a simulation computer model of subsystems and flight phenomena affecting the energy consumption during the flight. The modular construction of the simulation model allows the use of various details of simulation models for different stages of project development. The use of the HESS solution as well as the method of its design makes it possible to overcome the basic inconvenience of using electric drives in all types of vehicles, ie reconciling sufficient temporary operational parameters of the drive and long-term operation. In addition to...

MATEC Web of Conferences

Nowadays, worldwide environmental issue, associated to reduction of pollutant and greenhouse emissions are gaining considerable attention. Aviation sector contribution to the whole CO2 released accounts to around 2%, but it is expected to grow in the next future due to increase of demand. Probably, combustion engine design and fuel efficiency have already reached their optimum technology level and only a breakthrough as hybrid-electric propulsion could be able to satisfy the new international more demanding requirements. However, an improvement of the technology readiness level of hybrid-electric propulsion is strongly necessary and many operational and safety challenges should be addressed. In the work here reported, a hybrid-electric model was designed and developed for general aviation aircrafts, by means of the Mathworks® Matlab – Simulink 1D/0D simulation environment. Both thermal and electric energy storage units, transmission systems and power management devices were consider...

Journal of Aircraft

This paper proposes a conceptual methodology for designing vertical takeoff and landing aircraft with a hybridelectric propulsion system as an alternative to facilitate intercity missions for urban air mobility. Four new modules are developed to consider the diversity of configurations, flight mechanisms, and hybrid-electric propulsion system architectures. The flight-analysis module is proposed to account for various lift-and thrust-generating devices. The hybrid-electric propulsion system sizing module is modified for the vertical takeoff and landing aircraft by additionally considering transition flight. Based on a new proposed battery charge/discharge criterion, the mission-analysis module is constructed to predict the battery capacity and fuel consumption required for a given mission. The weight-estimation module is also developed considering the weight of the mechanical and electric powertrains. The proposed methodology is demonstrated by designing an urban air mobility vehicle and comparing the results with those of other sizing tools. A systematic comparative study and design optimization are carried out to highlight the improvement in the performance of the hybrid-electric-powered vertical takeoff and landing aircraft compared to its battery-driven counterpart. The extended mission range of the designed aircraft presents the possibility of intercity urban air mobility vehicles.