Electrified Aircraft Trade-Space Exploration

Krüger, Michael; Byahut, Saakar; Uranga, Alejandra; Dowdle, Aidan P.; Gonzalez, J.; Hall, David K.

doi:10.2514/6.2018-4227

Cited by 20 publications

(7 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several such metrics exist for conventional aircraft, such as the payload-range efficiency (PRE = W PL R/W f ) [31], or the payload-fuel energy efficiency (PFEE = W PL R/E f ) [32]. Alternative metrics have also been used for hybrid-electric aircraft, such as the energy-specific air range (ESAR = dR/dE) [33], the cost-specific air range (COSAR) [26], or the productivity-specific energy consumption (PSEC = E/(m PL R)) [34], where the energy consumed E includes both fuel and battery energy. However, when quantifying the overall "efficiency" of the aircraft in terms of energy consumption, only the energy consumed during the nominal mission must be considered, and not the reserves.…”

Section: Figures Of Meritmentioning

confidence: 99%

Preliminary Sizing of a Hybrid-Electric Passenger Aircraft Featuring Over-the-Wing Distributed-Propulsion

Vries

Hoogreef

Vos

2019

AIAA Scitech 2019 Forum

View full text Add to dashboard Cite

This study compares a hybrid-electric aircraft featuring a propulsive empennage and overthe-wing, distributed-propulsion to a conventional regional turboprop. The impact of multiple design parameters, mission requirements, and technology assumptions on maximum takeoff mass and payload-range energy efficiency is evaluated, in order to illustrate the sensitivities of the design. A preliminary sizing method that incorporates aero-propulsive interaction effects is used to obtain rapid estimations. Results show that, for the baseline mission, the hybridelectric variant is 2.5% heavier and consumes 2.5% more energy than the reference aircraft. In this process, several key design guidelines and challenges for distributed-propulsion aircraft are identified. Firstly, when comparing a hybrid-electric configuration to a conventional one, each aircraft must be sized at its optimum cruise altitude for the same payload and range requirements. Secondly, the hypothetical advantages of distributed propulsion described in literature do not easily lead to a benefit at aircraft level, if the aero-propulsive interaction effects and associated dependencies are incorporated in the design process. Thirdly, the power-control parameters affect practically all characteristics of the aircraft, and the optimal control strategy is highly dependent on the aero-propulsive interaction. The results suggest that the proposed configuration can constitute a low-noise alternative for the regional transport market if the performance of the over-the-wing distributed-propulsion system is optimized.

show abstract

Section: Figures Of Meritmentioning

confidence: 99%

Preliminary Sizing of a Hybrid-Electric Passenger Aircraft Featuring Over-the-Wing Distributed-Propulsion

Vries

Hoogreef

Vos

2019

AIAA Scitech 2019 Forum

View full text Add to dashboard Cite

show abstract

“…The component build-up was then modified to account for the weights of the electrical components and to remove the conventional engine and fuel system. The assumptions with respect to the electrical components were varied based on three sets of technologies (current technology, conservative future, optimistic future) as generated from Freidrich and Robertson [22] and Kruger et al [23] and as shown in Table 1. Initial estimates are made for the battery, motor, and inverter weights based on the results of the first iterative process and technology assumptions.…”

Section: Methodsmentioning

confidence: 99%

Configuration Study of Electric Helicopters for Urban Air Mobility

et al. 2021

View full text Add to dashboard Cite

There is currently interest in the design of small electric vertical take-off and landing aircraft to alleviate ground traffic and congestion in major urban areas. To support progress in this area, a conceptual design method for single-main-rotor and lift-augmented compound electric helicopters has been developed. The design method was used to investigate the feasible design space for electric helicopters based on varying mission profiles and technology assumptions. Within the feasible design space, it was found that a crossover boundary exists as a function of cruise distance and hover time where the most efficient configuration changes from a single-main-rotor helicopter to a lift-augmented compound helicopter. In general, for longer cruise distances and shorter hover times, the lift-augmented compound helicopter is the more efficient configuration. An additional study was conducted to investigate the potential benefits of decoupling the main rotor from the tail rotor. This study showed that decoupling the main rotor and tail rotor has the potential to reduce the total mission energy required in all cases, allowing for increases in mission distances and hover times on the order of 5% for a given battery size.

show abstract

“…For simplicity in assessing initial results, this current work only models fully-electric configurations, where all vehicle power is stored in batteries. Hybrid-electric powertrains o er substantial range benefits over all-electric configurations [14], at the cost of increased complexity, local emissions, and noise. This range benefit would be expected to apply to both STOL and VTOL configurations; propulsion system architecture is another part of the design space over which the configurations should be compared.…”

Section: Design Mission Parametersmentioning

confidence: 99%

Model Development for a Comparison of VTOL and STOL Electric Aircraft Using Geometric Programming

Courtin

Hansman

2019

AIAA Aviation 2019 Forum

View full text Add to dashboard Cite

There is widespread interest in the use of electric aircraft for short missions in and around urban areas. Most of the vehicle configurations proposed for these missions are electric Vertical Takeo and Landing (VTOL) configurations, due to perceived limitations on the available infrastructure. Several recent studies have proposed electric Short Takeo and Landing (STOL) aircraft with externally blown flaps as viable alternatives for urban operations. One of the claimed benefits of STOL aircraft is increased mission performance (in terms of range, payload, or speed) compared to an VTOL aircraft of the same weight. This study discusses the development of the models necessary to investigates this claim for a variety of possible missions, available infrastructure sizes, and levels of technology. Preliminary mission spaces where STOL or VTOL aircraft are the most weight-e cient choice are identified. The analysis is done using geometric programming, a convex optimization framework that enables rapid design re-optimization over a broad mission space. F Flap deflection Wake circulation µ Wheel friction coe cient ' Velocity potential Horseshoe vortex circulation

show abstract

Electrified Aircraft Trade-Space Exploration

Cited by 20 publications

References 7 publications

Preliminary Sizing of a Hybrid-Electric Passenger Aircraft Featuring Over-the-Wing Distributed-Propulsion

Preliminary Sizing of a Hybrid-Electric Passenger Aircraft Featuring Over-the-Wing Distributed-Propulsion

Configuration Study of Electric Helicopters for Urban Air Mobility

Model Development for a Comparison of VTOL and STOL Electric Aircraft Using Geometric Programming

Contact Info

Product

Resources

About