bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regional jet retrofitting through multidisciplinary aircraft design
Authors: Mandorino Massimo , Vecchia Pierluigi Della , Nicolosi Fabrizio , Cerino Giovanni 
Published: February 2022

Abstract
Multidisciplinary collaborative aircraft design is applied to a 90 passengers regional jet aircraft retrofit, highlighting the impact on costs and performance. Two retrofitting packages have been considered: the re-engining of conventional power-plant platform with advanced geared turbofan and the on-board-system modernization, considering different level of electrification. Starting from a reference existing aircraft, the impact of retrofitting process has been carefully evaluated on capital costs and savings at industrial level through a developed methodology. At aircraft level, masses, performance, noise, and emissions have been computed with dedicated competences increasing the estimation reliability. Overall process is implemented in the framework of the AGILE 4.0 research project in a collaborative remote multidisciplinary approach. Results show that such retrofitting activities are expensive and must be evaluated since the design stage with a bottom-up approach requiring competences coming from designer experience to correctly define the process work-breakdown-structure and its implications.
Investigation of the impact of a particle foam insulation on frost buildup on the aircraft structure
Authors: Norrefeldt Victor , Riedl Gerhard 
Published: February 2022

Abstract
The aircraft insulation separates the thermally comfortable cabin interior environment from the extremely cold outside condition. However, the fabrication and installation of the insulation in the aircraft is a labour intensive task. Tailored, rigid particle foam parts could be a solution to speed up installation process. The presented study investigates the feasibility of such a concept from a hygrothermal point of view. Due to the temperature difference between the cold air trapped between aircraft skin and insulation on one side and the warm cabin air on the other side, a buoyancy induced pressure difference forms. This effect drives the warmer air through leakages in the insulation system towards the cold skin. Here, moisture contained in the air condenses on the cold surfaces, increasing the risk for uncontrolled dripping (“rain in the plane”) when it melts. Therefore, this study compares the frost build-up of different installations of a rigid particle foam frame insulation with the classical glass fiber capstrip. Tests are hosted in the Fraunhofer Lining and Insulation Test Environment chamber.
A motorized and remotely controlled Horizontal Tailplane for efficient WT testing
Authors: Berger Matthias , Flamini Luca , Pasta Roberto , Servadio Cesare , Adden Stephan , Seiler Jendrik , Flamini Luciano , Paletta Nicola 
Published: February 2022

Abstract
The H2020-Cleansky 2 project EULOSAM II supports the development and assessment of an innovative natural laminar aircraft wing by integrating innovative aerodynamic control surfaces and high lift technologies. The project focuses on the modification and completion of a WT-model to enable robust and efficient testing. EULOSAM II is a project funded by the EC through the Clean Sky 2 JU and carried out in cooperation with Dassault Aviation. In order to ensure efficient testing a key element of EULOSAM II was to develop and validate a solution to improve the WT test productivity, which was achieved by designing, manufacturing and testing a remotely controlled, actuated HTP which significantly reduces the time needed in the WT for model-configuration changes. The model under review is a business jet half-model, test will be performed in the ONERA F1 Wind Tunnel, at high Reynolds numbers and low Mach Numbers typical of high-lift conditions. This paper presents the outcome of the whole development process of the actuated solution. This development includes the mechanical design as well as the control-solution to be applied in the WT. Pre-Tests have been performed in order to show that the implemented solution is working well and is robust enough to enable smooth and productive testing operations. In this paper, details on the design as well as explanations on why specific solutions were down-selected and found to be most effective ones are presented. During the final development phase, to investigate the functionality and robustness of the system, ground tests have been conducted with the assembled model on test benches to save WT time and to enable faster troubleshooting. Actuating WT models are seen as key to increase WT test efficiency, therefore this is in particular interesting for WT-test which have high hourly test-costs. Lessons learned for future applications therefore will be given to discuss if solutions found so far can be extrapolated to other, comparable applications.
Analysis of the application of fuselage skin reinforcements with beam element representations in flexible full aircraft models for ditching simulations
Authors: Leon Muñoz C , Kohlgrüber D , Langrand B 
Published: February 2022

Abstract
The aim of this paper is the application of beam element representations for structural skin reinforcements in flexible full aircraft FE models used in ditching simulations. To verify this approach, it was initially analyzed on flexible reinforced bottom-aircraft panels under guided ditching conditions, considering also structural mesh size variations and partly corresponding fluid mesh densities. For this analysis two different numerical methods were used for comparisons, the coupled Finite Element-Smoothed Particle Hydrodynamics and the Arbitrary Lagrangian Eulerian methods. For the generation of the full aircraft model a multidisciplinary process chain approach and a standardized data format description are used. The beam element representations are considered for the modelling of skin reinforcement as well as other structures like cabin and cargo floor structures. By this approach, first time feasible full aircraft ditching simulations and the subsequent analysis of both global kinematics and the local fuselage structural response could be achieved.
System architectures for thermal management of hybrid-electric aircraft - FutPrInt50
Authors: Affonso Walter , Tavares RenataT. , Barbosa Felipe R. , Gandolfi Ricardo , dos Reis Ricardo J. N. , da Silva Carlos R. I. , Kipouros Timoleon , Laskaridis Panagiotis , Enalou Hossein Balaghi , Chekin Andrei , Kukovinets Aleksey , Gubernatorov Konstantin , Ravikovich Yury , Ivanov Nikolay , Ponyaev Leonid , Holobtsev Dmitry 
Published: February 2022

Abstract
Electric and Hybrid-Electric Aircraft (HEA) propulsion system designs shall bring challenges at aircraft and systems level, mainly in propulsion, electric and thermal management systems (TMS). The electrification of the propulsion system relies on large and high-power electrical equipment (e.g., electrical motors, converters, power electronics, batteries, and others) that dissipate heat at a rate at least one order of magnitude higher than conventional propulsion aircraft systems. As a result, high impacts on weight, drag and power consumption of the TMS/cooling systems at the aircraft level are expected. This paper proposes potential technologies to perform the thermal management of future electric and HEA, in the context of FUTPRINT50 project. For each technology, relevant aspects such as its integration to aircraft, safety, operational and maintenance impacts, certification, technologies readiness level (TRL) and the latest research works are analysed. A quantitative comparison of the several technologies is also proposed considering weight, volume, electric power consumption, pneumatic air flow and cooling air flow per cooling effect. Lastly, we present a set of potential TMS architectures for HEA.
Hybrid-electric and hydrogen powertrain modelling for airplane performance analysis and sizing
Authors: Khan YM , Rolando A , Salucci F , Riboldi CED , Trainelli L 
Published: February 2022

Abstract
This paper describes a framework for parametric modelling of hybrid-electric powertrain components for innovative airplane configurations. These models are used in scalability studies and performance analysis of novel propulsion architecture. The methodology involves culmination of these models in a set of tools specifically developed to study the initial and conceptual sizing of hybrid-electric aircraft. This allows quick parametric evaluation of various configurations based on components at different technology readiness levels, such as batteries and fuel cells. Characteristics and performance of the power-train components are evaluated using computational analysis as well as laboratory tests. This information is used to develop numerical models described in the paper and to validate the sizing of fundamental propulsion components. Applications to two variants of a commuter aircraft are given, one using a serial hybrid-electric architecture based on a thermal engine, and the other using a fuel-cell system fed by a gaseous hydrogen tank.
Intrinsic interfaces between additively manufactured metal and composite structures for use in electric propulsion engines
Authors: Pohl M. , Spitzer S. , Grothe R. , Weidermann Ch. , Gude M. 
Published: February 2022

Abstract
For electric aviation drive systems engines with significantly increased power density are required. Combining the technologies of additive manufacturing of metals with the technologies of fiber reinforced composites enables hybrid structures with same or increased functionality and lower mass. Rotors or housings in hybrid design have interfaces to adjacent structures are classically made of metal. Areas for remote load transmission or with increasing distance to the rotation axis can be made of carbon fiber reinforced plastic (CFRP). The interfaces between these two materials, required for such a hybrid metal-CFRP design, can be specifically designed by using the design options of additive manufacturing to fulfill the required functions with a the most even distribution of stress possible. However, the large number of degrees of freedom of the material and the geometry leads to great challenges for engineers in the development of such structures. Within the scope of this publication, an approach for the function-oriented design of a metal-CFRP rotor for an aviation electric motor is proposed (global design). A design and pre-dimensioning method for the intrinsic interface between the materials is presented (local design).
Influence Of Polymer Coating Thickness On Damage Tolerance And Residual Strength Of Composite Material
Authors: Kudryavtsev O A , Leshkov E V , Olivenko N A , Ignatova A V , Bezmelnitsyn A V 
Published: February 2022

Abstract
The low impact resistance of laminated polymer composites is a significant problem. Even barely visible impact damages can significantly decrease the residual strength of the composite. In this article, the effect of the thickness of a polymer coating based on hollow glass microspheres on the damage tolerance and residual strength of glass fibre-reinforced plastic (GFRP) was studied. 4 mm thick GFRP specimens with polymer coatings of different thicknesses were prepared. The thickness of the coatings varied from 0.4 mm to 1.2 mm. The specimens were tested on a vertical drop tower system with impact energies up to 25 J. The dimensions of the obtained defects were determined using infrared thermography. The residual strength of the specimens was determined using the Flexure-After-Impact protocol. It was found that the 1 mm thick coating with a surface density of 650 g/m2 made it possible to reduce the damaged area by 35% and to increase the residual flexural strength of the GFRP specimens by 27% in comparison with the uncoated ones.
Cost Optimized Avionics System – Navigation Solution for Small Aircraft Transportation Segment
Authors: Vaispacher Tomas , Sotak Milos , Kana Zdenek , Baranek Radek , Malinak Pavol , Kucera Matej 
Published: February 2022

Abstract
Modern navigation systems represent an inherent part of avionic equipment onboard all aircraft categories. The standard navigation performance typically defined by accuracy, integrity, availability, and continuity is now complemented by the system’s ability to reduce CO2 emissions and fuel consumption. This article describes current navigation system development executed by Honeywell International for SAT (Small Aircraft Transportation) segment defined by CS-MMEL ATA 34 Navigation. The proposed solution is based on INS/GNSS hybridization extended by other aiding sensors available onboard the aircraft. To create a technological solution that meets the system operational requirements of the segment and at the same time comply with SWAP-C (Size, Weight, And Power Consumption Related to Cost) requirements is the aim of this research activity. The article describes proposed integration architecture based on hybridized core and other aiding sensors, such as radar altimeter and magnetometer. The assessment of previously mentioned aiding sensors was performed and impact on navigation performance was determined. The emphasis was mainly put on Inertial Measurement Unit (IMU) meeting the low-cost requirement for the overall architecture. The IMU error model definition and long-term thermal chamber measurements are the main tools for understanding the stochastic behaviour of the IMU’s. The accuracy improvement is further supported by implementing SBAS corrections in INS/GNSS hybridization. This is not a usual navigation solution for SAT segment, since, typically, standalone GNSS receiver with SBAS is used instead. The Monte Carlo simulations were performed to compare the performance of the proposed solution against system and operational requirements. A proprietary Honeywell tool for these large-scale simulations is capable to simulate the navigation exercise anywhere on the Earth using pre-defined trajectories with specific duration and simulated GNSS constellation to reflect the impact of the satellite geometry.
Derivation of Top-Level Aircraft Requirements for Small Aircraft Transport by Modelling Demand in Europe
Authors: Will Florian , Flüthmann Nico , Eschmann Christian 
Published: February 2022

Abstract
Advancements in aircraft technologies and in the process of aircraft electrification allow for the design of new small aircraft transport (SAT) configurations with a significant impact on sustainability, travel time and operating cost. Additionally, the European Flightpath 2050 creates a European-wide political landscape to enable developments in that field to thrive. All this together provides an environment that promises to open new business opportunities in the form of new and revived mobility services. However, the described ecosystem raises the question of what demand exists for SAT and what top-level aircraft requirements (TLAR) need to be achieved to realize customer-centric SAT. Data of the existing traffic patterns in Europe is analyzed to create a demand model, derive the TLAR and ultimately lay the foundation for a successful European SAT transport system. Initially, traffic pattern data is collected with a resolution on county and city level, thereby ensuring a high accuracy of larger and smaller travel distances. Subsequently, to the data collection, the income distribution in European countries is analyzed and in combination with a Willingness To Pay (WTP) function the actual existing SAT demand is determined. The demand optimized TLAR are then derived by varying the demand models input parameters to maximize the demand. The above-described approach allows to extract the potential annual demand in Europe for a certain set of requirements, it also details how a single parameter effects the demand. Hence, it provides sensitivities to illuminate design focal points. In consideration of all the described factors the paper defines the TLAR, thereby enabling the design of new SAT configurations.
Key design and operation factors for high performance of C12A7:e-based cathodes
Authors: Post A. , Plaza J.F. , Toledo J. , Zschätzsch D. , Reitemeyer M. , Chen L. , Gurciullo A. , Siegel A. , Klar P. J. , Lascombes P. , Seifert B. 
Published: February 2022

Abstract
This work, based on an EU-funded project (NEMESIS), is summarising some of the results from the project activities on the research and development on electride-based cathode technology compatible with all kinds of electric propulsion (EP) systems requiring neutralization or electron emission. Further information describing in detail the performed tests and captured measurements can be found in the referenced documents of each section. Different cathode architectures and several emitter configurations with traditional and with alternative propellants are being developed and tested within the project, all of them using C12A7:e-electride material as thermionic electron source. Findings and conclusions derived from these multiple designs are allowing to figure out some of the key factors that determine the best performance of C12A7:e-electride based cathodes. In this work, a discussion of some of these key design and operation factors will be presented based both on the material characterization parameters, and on the performance tests carried out for the different cathode designs.
HERA Mission LIDAR Mechanical and Optical Design
Authors: Dias Nicole G. , Arribas Beltran N. , Gordo Paulo , Sousa Tiago , Marinho João , Melicio Rui , Amorim António , Livio Belegante , Michel Patrick 
Published: February 2022

Abstract
Near-Earth Objects (NEO) are the topic of several research studies, with objects smaller than 1km in size posing the most threats and being the less understood of this scientific domain. The Asteroid Impact and Deflection Assessment (AIDA) mission involves NASA and ESA with the main mission goal to perform and analyze the asteroid deflection using the Kinetic Impactor technique. The mission target is Didymos-B, a moon of a binary asteroid called Didymos. NASA oversees the Double Asteroid Redirection Test (DART probe), and ESA is responsible for HERA probe, that will measure the Dydimos-B deflection caused by the impact. The Light Detection and Ranging (LIDAR), the Radar, the Satellite-to-Satellite Doppler tracking, the Seismometer, and the Gravimeter are instruments integrated into HERA spacecraft. Information synergy between the instruments allows the detailed characterization of the asteroid including internal structure. This experiment allows further understanding and will provide important information to improve the current NEO understanding and modelling. In this paper, scientific advances related to the LIDAR instrument are reported, including the innovative optomechanical design resulting from thermal and mechanical optimizations. The LIDAR has a compact design and needs to withstand extreme conditions, such as radiative and thermal conditions, without compromise its high accuracy measurements. The LIDAR is a time-of-flight altimeter instrument that will measure the distances from the HERA spacecraft to the target. It provides information for a 3D topographic mapping and calculates the asteroid reflectivity. The measurements are to be performed at a distance from 500 m to 14 km while operations such as fly byes or landings remain a possibility.
Digital twins for prognostics of electro-hydraulic actuators: novel simplified fluid dynamic models for aerospace valves
Authors: Berri Pier Carlo , Vedova Matteo D.L. Dalla , Santaera Simone 
Published: February 2022

Abstract
In the design and development phases of electro-hydraulic actuators (EHAs) used for aircraft flight controls, it is often necessary to carry out accurate and high-fidelity fluid dynamics simulations to evaluate the system behaviour within its entire operating range and, if necessary, investigate its most critical issues. These high-fidelity simulations (nowadays achievable with different techniques and commercial software) generally become pretty expensive from a computational perspective. Therefore, especially in the preliminary design phases or implementing system health monitoring algorithms (in real-time), the need to adopt simplified models emerges definitely (albeit capable of guaranteeing the appropriate level of detail and accuracy). These simplified models are also essential for developing effective and reliable model-based prognostic strategies capable of performing early health assessments of EHA valves. This work proposes a new lumped-parameters simplified numerical model, which, despite having a very compact formulation and reduced computational costs, simulates the internal fluid dynamics of the valve, overcoming some critical issues typical of other models available in the literature. It evaluates valve performance as a function of spool position and environmental conditions (e.g. supply pressure), better-assessing flow rate feedback, internal leakages, and other operating conditions (e.g. spool fine adjustment, pressure supply variable, overpressure, or water hammer). The performance of this numerical model is evaluated comparing with other simplified models published in the literature. Moreover, it is validated with a high-fidelity digital twin that simulates the behaviour of the valve, taking into account the geometry of the spool, the properties of the hydraulic fluid, and the local internal fluid-dynamics (laminar or turbulent regime, cavitation, etc.).
Analytical Design of Conventional and Electrical Aircraft Environmental Control Systems
Authors: Munjulury Raghu Chaitanya , Devadurgam Hemanth , Rajagopal Soorya , Krus Petter 
Published: February 2022

Abstract
Environmental control systems hold vital importance as they are responsible for aircraft cabin air ventilation and passenger comfort. This paper presents an analytical design of both Conventional & Electrical environmental control systems. The result of the estimated design is represented in a geometrical model that gives freedom to visualize various options in the conceptual design process, using Knowledge-based engineering application as a base for the design and methodology. Flexibility in the model enables the user to control the size and positioning of the system and sub-systems associated with it. The number of passengers serves as the driving input and the three-dimensional model gives the exact representation concerning the volume occupied and dependencies on the number of passengers. It also provides a faster method to alter the system to user needs with respect to the number of air supply pipes, number of ducts, and pipe length.
Real Estate Advisory Drone (READ): system for autonomous indoor space appraisals, based on Deep Learning and Visual Inertial Odometry
Authors: Quattrini A , Mascheroni A , Vandone A , Coluzzi M , Barazzetti A , Cecconi F , Leidi T 
Published: February 2022

Abstract
The present paper describes the development of a mobile platform as a support of the real estate appraisal procedure. Currently, the estate evaluation is performed by an expert that manually collects data, performs measurements, and grabs pictures of the inspected unit to finally evaluate its commercial value. The READ project aims at automatizing this process by developing a solution based on a mobile unit (drone or tablet) able to navigate the indoor environment and record data, which will be later processed on the cloud. To accomplish all these tasks, the platform is equipped with cameras, a LiDAR sensor, and a data process unit, with the goal of 1) understanding its motion and localization; 2) reconstructing a 3D map of the inspected space; 3) performing image-based analyses applying AI algorithms enabling the identification of the indoor space (e.g. bedroom or kitchen), the counting and the classification of furniture objects, and the detection of building imperfections or frauds. Tests have been performed in different scenarios providing promising results, laying the foundations for bringing these technologies into a real operational context.