Approach to the Weight Estimation in the Conceptual Design of Hybrid-Electric-Powered Unconventional Regional Aircraft

Abstract

The present work deals with the development of an innovative approach to the weight estimation in the conceptual design of a Hybrid-Electric-Powered (HEP) Blended Wing Body (BWB) commercial aircraft. In the last few decades, the improvement of the environmental impact of civil aviation has been the major concern of the aeronautical engineering community, in order to guarantee the sustainable development of the system in presence of a constantly growing market demand. The sustained effort in the improvement of the overall efficiency of conventional aircraft has produced a new generation of vehicles with an extremely low level of emissions and noise, capable of covering the community requirements in the short term. Unfortunately, the remarkable improvements achieved represent the asymptotic limit reachable through the incremental enhancement of existing concepts. Any further improvement to conform to the strict future environmental target will be possible only through the introduction of breakthrough concepts. The aeronautical engineering community is thus concentrating the research on unconventional airframes, innovative low-noise technologies, and alternative propulsion systems. The BWB is one of the most promising layouts in terms of noise emissions and chemical pollution. The further reduction of fuel consumption that can be achieved with gas/electric hybridisation of the power-plant is herein addressed in the context of multidisciplinary analyses. In particular, the payload and range limits are assessed in relation to the technological development of the electric components of the propulsion system. The present work explores the potentialities of an energy-based approach for the initial sizing of a HEP unconventional aircraft in the early conceptual phase of the design. A detailed parametric analysis has been carried out to emphasise how payload, range, and degree of hybridisation are strictly connected in terms of feasible mission requirements and related to the reasonable expectations of development of electric components suitable for aeronautical applications.

Numerical Characterisation of the Aeroacoustic Signature of Propeller Arrays for Distributed Electric Propulsion

“…The ARTEM consortium, coordinated by the German Aerospace Centre (DLR), is composed by 24 partners from 10 European countries including Russia (Belgium, France, Germany, Italy, The Netherlands, United Kingdom, Romania, Slovenia, Switzerland, Russian Federation). In this context, important developments of the FRIDA framework have allowed the introduction of HEP and DP within the optimal design process [8]. Specifically, a revised mass estimation procedure, accounting for the electric components weight has been implemented in addition to nonlinear scaling laws for the distributed propulsion system mass estimate.…”

“…This layout turns out to have a reduced wetted surface to volume ratio, exploiting a greater useful volume compared to the standard configurations. It is characterised by a large centre body surface which lends itself well to mount distributed electric-driven propellers and Boundary-Layer-Injection (BLI) layouts [4,7,8]. Several theoretical studies and experimental campaigns have demonstrated that the BWB aerodynamic efficiency can be considerably improved [9], also due to the reduced interference drag.…”

“…Here, the aircraft layout has been optimised and analysed within the in-house Multidisciplinary Conceptual Robust Design Optimisation (MCRDO) framework FRIDA (Framework for Integrated Design of Aircraft) [8,27,28]-the optimised configuration has been tested over the design mission and the flight mechanics variables successfully derived. The initial propeller geometry has been designed using a lifting-line theory method [29,30].…”

Future Aircraft and the Future of Aircraft Noise

“…The long-range configuration denominated BOLT (Blended wing body with Optimised Low-noise Technologies) has been equipped with two last-generation UHBR turbofan engines, with an expected payload of 400 passengers in a two-classes cabin layout. The shortrange REBEL (REgional Blended-wing-body Electric-propelled), although originally conceived to be equipped with hybrid electric propulsion, has been actually designed in two versions: a baseline configuration equipped with conventional technologies and turbofan engines (REBEL-C) and the REBEL-HEP propelled by a distributed hybrid electric system [15][16][17]. A pictorial rendering of the ARTEM BWB fleet is presented in Fig.…”

Structural design and experimental verification of a novel split aileron wing

“…To maximize the aerodynamic efficiency and decrease the structural weight of wing, blended wing body (BWB) technology [1][2][3][4] could be usually introduced, which is mainly for military unmanned aerial vehicles (UAVs) and high-speed aircraft. Indeed, the demands of smoothness surface and lighter weight for small and low speed (<50m/s) UAV lead designers to think out such a perfect plane, which has the ability to control the rolling motion of the aircraft without a traditional hinged aileron.…”