bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimates of the climate impact of future small-scale supersonic transport aircraft – results from the HISAC EU-project
Authors: Grewe V. , Plohr M. , Cerino G. , Muzio M. Di , Deremaux Y. , Galerneau M. , Martin P. de Saint , Chaika T. , Hasselrot A. , Tengzelius U. , Korovkin V. D. 
Published: February 2016

AbstractThe climate impacts of three fleets of supersonic small-scale transport aircraft (S4TA) are simulated. Based on characteristic aircraft parameters, which were developed within the EU-project HISAC, emissions along geographically representative trajectories are calculated and in addition the resulting changes in the atmospheric composition (carbon dioxide, ozone layer, water vapour) and climate (near surface global mean temperature) are deduced. We assume a fleet development with an entry in service in 2015, a full fleet in 2050. The results show a temperature increase of 0·08mK (0·07-0·10mK) with only small but statistically significant variations between the configurations, leading to a minimum climate impact for a weight optimised and hence lower flying aircraft. A climate impact ratio of 3·0 ± 0·4 between a S4TA and its subsonic counterpart is calculated, which is considerable less than for previous supersonic fleets because of a lower flight altitude, leading to smaller water vapour impacts.
Flight control using pin-protuberances for blunted cones
Authors: Samar R. , Zahir S. , Khan M. A. 
Published: February 2016

AbstractThis paper presents the concept of using cylindrical pins as short protuberances for trajectory control of a blunted cone in the supersonic and hypersonic regimes. Supersonic and hypersonic flow interactions for cylindrical protuberances, installed on a blunt cone are studied for their aerodynamic effects. The utility of these protuberances for aerodynamic control and trajectory shaping of a re-entry cone are explored. Static aerodynamic coefficients in the Mach range of 2–9·7 at various incidences are computed. The pressure distribution along the vehicle longitudinal axis in the presence of the pin-protuberance is studied using CFD analysis. With the altered pressure distribution, a net increase in the aerodynamic force is obtained which can be actively utilised for flight control and maneuvering of the vehicle during re-entry. After quantifying the aerodynamic effects of the protuberance, it is modelled and used as an effective actuation mechanism for flight feedback control. It is shown that this can work as an effective control device for Mach numbers less than five. An actuator design for insertion/retraction of the protuberance is presented and modelled, and a robust controller is synthesised which can in real time govern the position of the protuberance to control the flight attitude angle to achieve a desired trajectory. The controller takes in measurements of the vehicle’s pitch angle and actuates the pin height continuously to control the pitch angle to a desired value. The control performance is demonstrated on a high fidelity six degrees-of-freedom (6-DOF) nonlinear flight simulation.
Design and realisation of a two-seater aircraft powered by fuel cell electric propulsion
Authors: Romeo Giulio , Borello Fabio 
Published: February 2016

AbstractThe main objective of the project is to develop and validate the use of a fuel cell based power system for the propulsion of more/all electric aircraft. The Rapid 200-FC two-seater electric-motor-driven aeroplane which is powered by fuel cells is at present being completed and will be validated during a flight test in Autumn 2009. Several configurations have been evaluated in order to install the new energy and propulsion system on board while maintaining the centre of gravity within allowable limits. The fuel cell system and the electric motor are being integrated on board. The FC stack will be able to deliver a maximum continuous power of 20kW. A battery pack has to guarantee another 20kW of maximum continuous power for a limited time period (15 minutes), during take-off, climbing and, in the case of emergency, during landing.The main goal of the project is to validate the overall high performance of an all electric aircraft system which is capable of remaining aloft for one hour. A parametric analysis has also been carried out to evaluate which key technologies influence the performance of future aircraft to the greatest extent.
Flutter control using resistively shunted piezoceramics
Authors: Kandagal S. B. , Venkatraman K. 
Published: February 2016

AbstractThis paper investigates the feasibility of flutter control using resistively shunted piezoceramics. 2D aerofoil model is elastically restrained in heave and pitch by a set of leaf springs modeled as Bernoulli-Euler beams. The piezoceramic transducers are bonded to the leaf springs. Unsteady aerodynamic theory is used to solve the flutter determinant incorporating the additive damping terms due to resistive shunting. Tuned dampers realised by resistive shunted piezoceramics in heave and pitch springs could enhance flutter speed in the range 25-50 % based on additive damping of 10 % achieved due to resistive shunting of piezoceramics in either pitch spring, heave spring or both.
Operation of small sensor payloads on tactical sized unmanned air vehicles
Authors: Patterson M. C. L. , Brescia A. 
Published: February 2016

AbstractThe miniaturisation of sensors has in recent years led to the ability to provide multiple sensor operations from a single Unmanned Aircraft System (UAS) platform. Multiple UAS platforms can be synchronised to link devices from separate UAS platforms thus proving a powerful capability for data collection, while opening up interesting opportunities in the way data is retrieved and used. A range of new sensors being investigated will be discussed with reference to selected case studies that have taken place. As we move into an increasingly growing, data rich environment, data management, quality and pedigree will become of increasing importance. Operations for both defence and non-defence applications will be discussed with reference to the present capability and what is required in future systems. This paper describes some of the sensors currently being evaluated. In the coming years it is expected that we will see a sharp increase in the use of small tactical sized autonomous vehicles in general and a large growth in the capability of the payloads being used.
An innovative evaluation platform for new aircraft concepts
Authors: Schmollgruber P. , Gobert J.-L. , Gall P.-E. , Goraj Z. , Jentink H. W. , Näs A. , Voit-Nitchmann R. 
Published: February 2016

AbstractWithin the European project NACRE (New Aircraft Concept REsearch), a team of research centres and universities focuses on the assessment of a test facility in the form of a flying platform. The goal of this Innovative Evaluation Platform (IEP) is to offer engineers a new tool to investigate areas of interest during the early design phases of advanced aeronautical systems.After an initial phase during which the potential benefits of such a platform have been demonstrated, the go-ahead for the IEP design and manufacturing has been given. In this second phase, a lot of attention has been brought to the system specifications since the platform has to meet the requirements of both an aerial vehicle and a test facility. The subsequent design process followed a stringent course of actions to achieve the design of a competitive test facility. The consortium aims for a final integration and flight trials in fall 2009.
Aviation and climate change: confronting the challenge
Authors: Bows A. 
Published: February 2016

AbstractEach year greenhouse gas emissions remain high the climate mitigation and adaptation challenges grow. The economic downturn was already in train in 2008, yet concentrations of CO2 increased unabated. Without concerted effort across all sectors there will be little chance of avoiding ‘dangerous climate change’ and the aviation sector has a clear role to play. Current and forthcoming technologies, operational practices and behavioural change offer widespread opportunities for other sectors to mitigate their CO2 emissions in absolute terms, but as they do so, aviation will become an increasingly important player. By comparing a range of global cross-sector emission scenarios with existing aviation projections, this paper illustrates the importance of understanding the future context with regard to other sectors when assessing the aviation industry’s potential impact. Given growth projections for aviation and the relatively slow pace of technological change, aviation’s proportion of 2050 global CO2 emissions is low only in those global cross-sector emission scenarios where there is a high probability of ‘dangerous climate change’. For a ‘reasonable’ (>50%) chance of avoiding ‘dangerous climate change’, the most technologically radical scenarios for aviation make up 15% of global CO2 in 2050 and conventional scenarios exceed the carbon budget entirely. Only by recognising that aviation’s currently projected emissions are incompatible with avoiding ‘dangerous climate change’ can the industry fully grasp the challenge of accelerating innovation and managing demand to deliver a more sustainable route to 2050 and beyond.
Exact strip analysis and optimum design of aerospace structures
Authors: Kennedy D. , Featherston C. A. 
Published: February 2016

AbstractMinimisation of airframe mass reduces the costs of materials and manufacturing, as well as fuel consumption and atmospheric emissions. Fast, reliable analysis tools are required during preliminary design, when many alternative configurations and load cases are considered. The modelling and computational costs of finite element analysis are avoided by employing exact strip solutions of the governing differential equations, using the Wittrick-Williams algorithm to solve the resulting transcendental eigenproblems of buckling and vibration. This paper reviews recent enhancements to the exact strip method for analysis and optimum design of aerospace structures, using the specialist software VICONOPT. Lighter composite panels can be designed by obtaining reliable estimates of the reduced postbuckling stiffnesses when loaded in compression and shear. Further advances include discrete optimisation of layer thicknesses to allow for practical composite manufacturing constraints, vibration constraints, and a newly extended multi-level interface combining finite element analysis of a whole wing with exact strip postbuckling design of individual panels.
Application of a knowledge based design methodology to support fuselage panel design
Authors: van der Elst S. W. G. , Tooren M. J. L. van , Vermeulen B. , Emberey C. L. , Milton N. R. 
Published: February 2016

AbstractKnowledge is a vital component of engineering design. Computer systems enriched with logic and engineering knowledge can support engineering design by automating repetitive and time-consuming processes. This automation is enabled using knowledge based engineering (KBE) techniques and can be obtained using dedicated KBE systems or augmented CAD systems, already pervasive throughout engineering industry. The development of these KBE applications is supported by a six-phase development process ranging from engineering process analysis to software development to business implementation. Distinctions and similarities exploiting alternative KBE platforms are addressed for each phase of the development process. An example KBE application is discussed, supporting the design of laminate aircraft fuselage panels. The implementation of the application is emphasised and five key-aspects required for a successful implementation are defined.
Maximum entropy approach to the identification of stochastic reduced-order models of nonlinear dynamical systems
Authors: Arnst M. , Ghanem R. , Masri S. 
Published: February 2016

AbstractData-driven methodologies based on the restoring force method have been developed over the past few decades for building predictive reduced-order models (ROMs) of nonlinear dynamical systems. These methodologies involve fitting a polynomial expansion of the restoring force in the dominant state variables to observed states of the system. ROMs obtained in this way are usually prone to errors and uncertainties due to the approximate nature of the polynomial expansion and experimental limitations. We develop in this article a stochastic methodology that endows these errors and uncertainties with a probabilistic structure in order to obtain a quantitative description of the proximity between the ROM and the system that it purports to represent. Specifically, we propose an entropy maximization procedure for constructing a multi-variate probability distribution for the coefficients of power-series expansions of restoring forces. An illustration in stochastic aeroelastic stability analysis is provided to demonstrate the proposed framework.
Numerical investigation of the role of hyper-mixers in supersonic mixing
Authors: Desikan S. L. N. , Kumaran K. , Babu V. 
Published: February 2016

AbstractIn this numerical study, the role of hyper-mixers on supersonic mixing is investigated for six different strut configurations. To this end, 3D, compressible, turbulent, non-reacting flow calculations with air as the secondary injectant have been carried out. A qualitative comparison of the predictions with experimental results is made through Schlieren and Mie scattering images. A quantitative evaluation of the predictions is made by comparison with experimentally measured exit stagnation pressure, wall static pressure and the degree of unmixedness. Based on these results, three strut configurations have been selected for carrying out simulations with hydrogen as the injectant. Results from the hydrogen simulations are compared with the predictions using air and also across the strut configurations. The results clearly demonstrate that castellated strut configurations are very effective in enhancing mixing in such high speed flows.
6U CubeSat design for Earth observation with 6▪5m GSD, five spectral bands and 14Mbps downlink
Authors: Tsitas S. R. , Kingston J. 
Published: February 2016

AbstractThe design of a 6U CubeSat including spacecraft systems and imaging payload is described for an Earth observation mission. From a Sun synchronous orbit at an altitude of 600km the design enables imaging with a 6.5m GSD, an optical MTF (on axis) of >59% at half Nyquist and >35% at Nyquist, a 26km swath, 12 bit digitisation and SNR of 120-200:one in five spectral bands; blue, green, red, red edge and near infrared. Data can be downlinked at the rate of 14 Mbps to a 3.7m S band ground station. This design allows an 8kg CubeSat to perform Earth observation missions equivalent to those of current 50-150kg microsatellites, with a corresponding reduction in cost.
Computer model for numerical simulation of emergency evacuation of transport aeroplanes
Authors: Hedo J. M. , Martínez-Val R. 
Published: February 2016

AbstractThe present paper describes a new, agent-based computer model that can simulate the evacuation of narrow body transport aeroplanes in the conditions prescribed by the airworthiness regulations for certification. The input data are extracted from a complete plan view of the cabin. The results include full egress details of all occupants, passengers and crew-members, and the most significant evacuation figures and diagrams. The model has been tuned and verified with real data of narrow body certification demonstrations. Numerical simulations of six narrow body aircraft, representative of current designs, show the capabilities of the model and provide relevant information on the relationship between cabin features and emergency evacuation results. Although the computer model has been developed for helping in the certification process it would be useful too in the design of new cabins.
The impact of flight simulation in aerospace
Authors: Allerton D. J. 
Published: February 2016

AbstractThis paper explains how flight simulation has made a major contribution to flight safety over the last thirty years to become critical to the operation of civil airlines and military organisations. It not only provides effective training, but for many flight training organisations has reduced the cost of flight training significantly. The paper outlines the increasing role of flight simulation covering flight training and research and development of aircraft and systems. The contribution of the flight simulation industry to the UK economy, in terms of both employment and revenue, is highlighted.The paper focuses on advances in the underpinning technologies of flight simulation, including mathematical modelling, real-time computation, motion actuation, visual image generation systems and projection systems.The paper also summarises the broadening roles of flight simulation; from part-task trainers to zero flight-time training in civil aviation; in military aviation, extending to combat domes and mission rehearsal; in defence procurement, where synthetic environments are used widely in evaluation studies prior to major project commitments; in aircraft development, providing powerful design tools to enable system designers to evaluate prototype systems.As a result of the acceptance of flight simulation in flight training, the use of simulators has been standardised throughout the world, with formal programmes of simulator qualification. These regulations, drawn up with the help of the RAeS Flight Simulation Group, ensure consistency for operators, regulators and manufacturers; the status of these regulations is outlined.The paper concludes by reviewing the lessons learnt by the flight simulation industry over the last thirty years and summaries the potential areas of growth, which will lead to simulation becoming widespread throughout many industries, in addition to the aerospace industry.
Modelling and vibration of a non-classical tilt-rotor wing system
Authors: Song O. , Kwon H. D. , Librescu L. 
Published: February 2016

AbstractProblems related with the mathematical modelling and eigenvibration of a tiltrotor aircraft-wing system built up of anisotropic composite materials are investigated. The wing-mounted rotor that can tilt from the vertical position to a horizontal one is modelled and analysed from the vibrational point of view. In this sense, its behaviour is analysed as a function of the mass size, mass moment of inertia, tilt angle and spin speed of the spinning rotor and of its location along the wing span. While the rotor is considered to be rigid, the aircraft wing is modelled as a thin-walled beam that features a doubly-symmetric cross-section contour and incorporates the elastic coupling between flap-lag-transverse shear, on one hand, and between extension-twist, on the other hand. Numerical simulations are provided and pertinent conclusions are outlined.
A change in the calculated impact of supersonic aircraft NOx emissions on the atmosphere
Authors: Dessens O. , Rogers H. L. , Pyle J. A. 
Published: February 2016

AbstractNew model calculations suggest that the potential impact on the atmosphere of a future fleet of supersonic aircraft, for the year 2015, is highly dependent upon the amount of nitrogen oxides (NOx) emitted from the fleet. This result contrasts with the IPCC assessment which suggested that the impact of supersonic aircraft on the atmosphere was primarily through the role of water vapour emissions both on atmospheric ozone and climate change. These new findings are extremely important for atmospheric scientists, the aviation industry and policy makers, highlighting the importance of further development of low NOx combustors for supersonic aircraft, an aspect which has been largely ignored following the IPCC Special Report.
Investigation on the aerodynamic performance of an ejection seat
Authors: Chen D. H. , Wu W. H. , Wang J. J. , Huang Y. 
Published: February 2016

AbstractA unique experimental method is used, in combination with numerical calculation and engineering estimation, to study the aerodynamic performance of an ejection seat at M = 0·60, 0·90 and 1·20, angles-of-attack α = 0°~360°, and sideslip angles (β = 0°~–90°. Several basic characteristics of the aerodynamic performance are explored. The normal force of the ejection seat varies in a sinusoidal way and the axial force in a cosinoidal way, with the angle-of-attack. The model is statically unstable longitudinally at most attitude angles and the longitudinal stability could be improved by a stabiliser. These characteristics result from a large low pressure area caused by the leeward separation and the windward high pressure area in the ejection seat flow field, at all α, due to the blunt configuration. A set of engineering calculation formulae is deduced, based on the aerodynamic characteristics of the ejection seat.
Use of Global Positioning System velocity outputs for determining airspeed measurement error
Authors: Gratton G. B. 
Published: February 2016

AbstractSeveral methods have been derived since the advent of GPS (Global Positioning System) receivers in aircraft cockpits by which these receivers may be used to calibrate these aircraft’s other instrumentation; in particular the pitot-static system. This paper presents the four most suitable methods, two of which have been developed by the author. These methods are shown with a common symbology, and their strengths, weaknesses, analysis and operational use are compared.
Aircraft cost modelling using the genetic causal technique within a systems engineering approach
Authors: Curran R. , Castagne S. , Early J. , Price M. , Raghunathan S. , Butterfield J. , Gibson A. 
Published: February 2016

AbstractThe paper is primarily concerned with the modelling of aircraft manufacturing cost. The aim is to establish an integrated life cycle balanced design process through a systems engineering approach to interdisciplinary analysis and control. The cost modelling is achieved using the genetic causal approach that enforces product family categorisation and the subsequent generation of causal relationships between deterministic cost components and their design source. This utilises causal parametric cost drivers and the definition of the physical architecture from the Work Breakdown Structure (WBS) to identify product families. The paper presents applications to the overall aircraft design with a particular focus on the fuselage as a subsystem of the aircraft, including fuselage panels and localised detail, as well as engine nacelles. The higher level application to aircraft requirements and functional analysis is investigated and verified relative to life cycle design issues for the relationship between acquisition cost and Direct Operational Cost (DOC), for a range of both metal and composite subsystems. Maintenance is considered in some detail as an important contributor to DOC and life cycle cost. The lower level application to aircraft physical architecture is investigated and verified for the WBS of an engine nacelle, including a sequential build stage investigation of the materials, fabrication and assembly costs. The studies are then extended by investigating the acquisition cost of aircraft fuselages, including the recurring unit cost and the non-recurring design cost of the airframe sub-system. The systems costing methodology is facilitated by the genetic causal cost modeling technique as the latter is highly generic, interdisciplinary, flexible, multilevel and recursive in nature, and can be applied at the various analysis levels required of systems engineering. Therefore, the main contribution of paper is a methodology for applying systems engineering costing, supported by the genetic causal cost modeling approach, whether at a requirements, functional or physical level.