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Viewing 121 to 150 of 20077
2017-09-19
Technical Paper
2017-01-2164
Markus Kintscher, Hans Peter Monner
Abstract Drag reduction technologies in aircraft design are the key enabler for reducing emissions and for sustainable growth of commercial aviation. Laminar wing technologies promise a significant benefit by drag reduction and are therefore under investigation in various European projects. However, of the established moveable concepts and high-lift systems, thus far most do not cope with the requirements for natural laminar flow wings. To this aim new leading edge high-lift systems have been the focus of research activities in the last five years. Such leading edge devices investigated in projects include a laminar flow-compatible Kruger flap [1] and the Droop Nose concept [2, 3] and these can be considered as alternatives to the conventional slat. Hybrid laminar flow concepts are also under investigation at several research institutes in Europe [4].
2017-09-19
Technical Paper
2017-01-2163
T. P. Aniruddhan Unni
Abstract The automotive underbody diffuser is an expansion device which works by speeding up the air flowing underneath a vehicle. This reduces the pressure below the vehicle thereby increasing downforce. When designed properly, it can lead to a massive gain in downforce and even a reduction in drag. However, a majority of the research and development is restricted to motorsport teams and supercar manufacturers and is highly secretive. Most of the publicly available research has been done for very simple shapes (bluff bodies) to study the effects of ground clearance and rake angle. Very little research has been done for complex geometries with vanes, flaps and vortex generators. This paper aims to investigate the effects of the addition of vanes/strakes and flaps, their location as well as angle, on diffuser performance. Computational Fluid Dynamics simulations have been carried out using three dimensional, steady state RANS equations with the k-ε turbulence model on STAR CCM+ V9.06.
2017-09-19
Technical Paper
2017-01-2162
Narayanan Komerath, Nandeesh Hiremath, Dhwanil Shukla, Joseph Robinson, Ayush Jha, Arun Palaniappan
Abstract This paper brings together three special aspects of bluff-body aeromechanics. Experiments using our Continuous Rotation method have developed a knowledge base on the 6-degree-of-freedom aerodynamic loads on over 50 different configurations including parametric variations of canonical shapes, and several practical shapes of interest. Models are mounted on a rod attached to a stepper motor placed on a 6-DOF load cell in a low speed wind tunnel. The aerodynamic loads are ensemble-averaged as phase-resolved azimuthal variations. The load component variations are obtained as discrete Fourier series for each load component versus azimuth about each of 3 primary axes. This capability has enabled aeromechanical simulation of the dynamics of roadable vehicles slung below rotorcraft. In this paper, we explore the genesis of the loads on a CONEX model, as well as models of a short and long container, using the “ROTCFD” family of unstructured Navier-Stokes solvers.
2017-09-19
Technical Paper
2017-01-2159
Federico Cappuzzo, Olivier Broca, Jeremy Leboi
Abstract To allow greater confidence in an aircraft system design in an ever increasing complex set of requirements, it becomes important to assess the interactions among systems and sub-systems earlier and with higher confidence. This study presents the Virtual Integrated Aircraft (VIA) methodology, which allows the integration of aircraft systems with virtual means. It aims to complement and precede physical integration, which is usually completed at the end of the validation and integration phase. LMS Imagine.Lab platform provides a means for applying this methodology. A simulation architecture, integrating models from different platforms, is built and simulations are run on a High Performance Computing (HPC) machine to cover multiple scenarios and therefore validate the selected architecture and pre-design in the early system development phases. A balanced selection of equipment, systems and subsystems are essential for the performance, safety, reliability and comfort.
2017-09-19
Technical Paper
2017-01-2158
Fernando Stancato, Luis Carlos dos Santos, Marcelo Pustelnik
Abstract A problem of interest of the aeronautical industry is the positioning of electronic equipment in racks and the associated ventilation system project to guarantee the equipment operational conditions. The relevance of the proper operation of electronic equipment increases considerably when high economical costs, performance reduction and safety are involved. The appropriate operational conditions of the electronic components happen when the working temperature of the equipment installed in the rack is inside a safety project temperature margin. Therefore, the analysis and modelling of heat transfer processes for aircraft rack design becomes mandatory. This paper presents a parametric study considering volumetric and superficial heat generation in electronic equipment within racks in an aircraft. Simulations were performed using the commercial CFD Fluent code and results were compared to experimental data.
2017-09-19
Technical Paper
2017-01-2155
Michal Salacinski, Piotr Broda, Piotr Samoraj
Abstract Polish Armed Forces are currently operating hundred helicopters belonging to Mi family. Metal fuselage is usually resistant to the battle and the human factor. Unfortunately, metal rotor blades of Mi helicopters are sensitive to operating conditions. Single blade is made from monolithic aluminum spar and mutually separated trailing sections, which are bonded to the spar. The sections are constructed of metal sandwich panels. During aggressive military operating conditions blades sections are often damaged by debonding from the spar, fatigue cracks of section skin, dents and perforations as well as erosion. The manufacturer assumed that structurally damaged sections should be exchanged. Provided repair technologies are applied only to cosmetic damages. Unfortunately, there is a limit to number repairs which prevents replacement of two neighboring sections due to the high temperature of curing cycle during the section replacement.
2017-09-19
Technical Paper
2017-01-2141
Fengmei Li, Peng Ke
Abstract For the ice protection of the engine air induction part manufactured with low thermal conductivity composite material, the combined heating method using interior impingement and exterior air film has certain advantages. To study the influence of the external jet air film on the impingement characteristics of droplets, the numerical simulation method of three dimensional water droplet impingement based on Eulerian method was developed and verified by experimental data from references. The droplets impingement characteristics under three different blowing ratios and two different velocities were then investigated based on the configuration of 3D cylinder with two parallel jet holes.
2017-09-19
Technical Paper
2017-01-2140
Mario Marchetti, Guillaume Casteran, Celine Jobard, Bruno Saintot, Patrice Bourson, Marc Fontana
Abstract Aircrafts and runways de-icing operations with anti-icing fluids are still the most commonly used methods. In the specific case of aircrafts, they do contain glycols. Nevertheless, since two decades now, major environmental concerns are raised, along with important associated costs. Furthermore, once applied either on aircrafts or on runways, these fluids are diluted because of water brought from adverse weather conditions (rain, snow, icy conditions), conducting to increasing the freezing point from a subzero level to 0°C. The characterization of the freezing points of these fluids is indeed crucial for safety reasons. For years now, Raman spectroscopy is used for the characterization of these fluids, specifically the freezing point. But the presence of dyes did perturb the usual spectroscopic characterization.
2017-09-19
Technical Paper
2017-01-2139
Guy Fortin
Abstract This paper reviews the current knowledge on super-hydrophobic coatings (SHC). Using an ideal super-hydrophobic surface patterned with identical cylindrical flathead posts forming a square network with constant periodicity, models are proposed to explain SHC, wear and ice adherence on SHC. The models demonstrate that SHC based on Cassie-Baxter state improve the bead mobility compared to SHC based on Wenzel state and more suitable for aircraft application. Their erosion resistance can be improved by increasing the post height and the hydrophobic material thickness. Their ice adhesion reduction factor (IARF) is better but SHC based on Cassie-Baxter state have a limitation to reduce ice adherence dependence on the surface pattern and IARF of the hydrophobic material. The bead mobility is calculated from advancing and receding water contact angles (WCA).
2017-09-19
Technical Paper
2017-01-2135
Alex Thirkell, Rui Chen, Ian Harrington
Abstract Electrification of aircraft is on track to be a future key design principal due to the increasing pressure on the aviation industry to significantly reduce harmful emissions by 2050 and the increased use of electrical equipment. This has led to an increased focus on the research and development of alternative power sources for aircraft, including fuel cells. These alternative power sources could either be used to provide propulsive power or as an Auxiliary Power Unit (APU). Previous studies have considered isolated design cases where a fuel cell system was tailored for their specific application. To accommodate for the large variation between aircraft, this study covers the design of an empirical model, which will be used to size a fuel cell system for any given aircraft based on basic design parameters. The model was constructed utilising aircraft categorisation, fuel cell sizing and balance of plant sub-models.
2017-09-19
Technical Paper
2017-01-2126
Ashutosh Kumar Jha, Gaurav Sahay, Adishesha Sivaramasastry
Abstract In aerospace industry, the concept of Integrated Vehicle Health Management (IVHM) has gained momentum and is becoming need of the hour for entire value chain in the industry. The expected benefits of lesser time for maintenance reduced operating cost and ever busy airports are motivating aircraft manufacturers to come up with tools, techniques and technologies to enable advanced diagnostic and prognostic systems in aircrafts. At present, various groups are working on different systems and platforms for health monitoring of an aircraft e.g. SHM (Structural Health Monitoring), PHM (Prognostics Health Monitoring), AHM (Aircraft Health Monitoring), and EHM (Engine Health Monitoring) and so on.
2017-09-19
Technical Paper
2017-01-2125
Mohammad Barkat, Vivek Karan, Pradeep N
Abstract The exponential increase in the number of aircrafts and air travelers has triggered new innovations which aim to make airline services more reliable and consumer friendly. Quick and efficient maintenance actions with minimum downtime are the need of the hour. Areas that have a large potential for improvement in this regard are the real time use of diagnostic data, filtering/elimination of nuisance faults and machine learning capabilities with respect to maintenance actions. Although, numerous LRUs installed on the aircraft generate massive amounts of diagnostic data to detect any possible issue or LRU failure, it is seldom used in real time. The turnaround time for LRU maintenance can be greatly reduced if the results of the diagnostics conducted during LRU normal operation is relayed to ground stations in real-time. This enables the maintenance engineers to plan ahead and initiate maintenance actions well before the aircraft lands and becomes available for maintenance.
2017-09-19
Technical Paper
2017-01-2107
Thorsten Kiehl, Jan Philip Speichert, Ethan Higgins, Ralf God
Abstract For an “end-to-end passenger experience that is secure, seamless and efficient” the International Air Transport Association (IATA) proposes Near Field Communication (NFC) and a single token concept to be enablers for future digital travel. NFC is a wireless technology commonly utilized in Portable Electronic Devices (PEDs) and contactless smart cards. It is characterized by the following two attributes: a tangible user interface and secured short range communication. While manufacturers are currently adapting PED settings to enable NFC in the flight mode, the integration and use of this technology in aircraft cabins still remains a challenge. There are no explicit qualification guidelines for electromagnetic compatibility (EMC) testing in an aircraft environment available and there is a lack of a detailed characterization of NFC equipped PEDs.
2017-09-19
Technical Paper
2017-01-2109
Kiran Thupakula
Abstract Airport environments consist of several moving objects both in the air and on the ground. In air moving objects include aircraft, UAVs and birds etc. On ground moving objects include aircraft, ground vehicles and ground personnel etc. Detecting, classifying, identifying and tracking these objects are necessary for avoiding collisions in all environmental situations. Multiple sensors need to be employed for capturing the object shape and position from multiple directions. Data from these sensors are combined and processed for object identification. In current scenario, there is no comprehensive traffic monitoring system that uses multisensor data for monitoring in all the airport areas. In this paper, for explanation purposes, a hypothetical airport traffic monitoring system is presumed that uses multiple sensors for avoiding collisions.
2017-09-19
Technical Paper
2017-01-2110
Ashutosh Kumar Jha, Prakash Choudhary
Abstract The complexity of software development is increasing unprecedentedly with every next generation of aircraft systems. This requires to adopt new techniques of software design and verification that could optimize the time and cost of software development. At the same time these techniques need to ensure high quality of software design and safety compliance to regulatory guidelines like DO-178C [1] and its supplements DO-330[2] and DO-331[3]. To arrive at new technologies one has to evaluate the alternate methods available for software design by developing models, integration of models, auto-code generation, auto test generation and also the performance parameters like time, effort, reuse and presentation needs to be evaluated. We have made an attempt to present summary of alternate design concept study, and edge of MBD over other design techniques.
2017-09-19
Technical Paper
2017-01-2113
Michael Schultz
Abstract Passenger boarding is always part of the critical path of the aircraft turnaround: both efficient boarding and online prediction of the boarding progress are essential for a reliable turnaround progress. However, the boarding progress is mainly controlled by the passenger behavior. A fundamental scientific approach for aircraft boarding enables the consideration of individual passenger behaviors and operational constraints in order to develop a sustainable concept for enabling a prediction of the boarding progress. A reliable microscopic simulation approach is used to model the passenger behavior, where the individual movement is defined as a one-dimensional, stochastic, and time/space discrete transition process. The simulation covers a broad range of behaviors and boarding strategies as well as the integration of new technologies and procedures.
2017-09-19
Technical Paper
2017-01-2117
Dirk H. Martinen, Marc Lagalaye, Julien Pfefferkorn, Jean Casteres
Abstract Currently, aircraft system Test Benches are often proprietary systems, specifically designed and configured for a dedicated System Under Test (SUT). Today, no standards for configuration, data communication, and data exchange formats are available for avionics Test Benches. This leads to high Test Bench development costs and redundant activities between aircraft system suppliers and airframers. In the case of obsolescence issues for test system components, it is very costly to replace the respective parts as a high integration and reconfiguration effort is required. In the scope of an R&T project, involving several test system suppliers and aircraft system suppliers as well as Airbus as an aircraft manufacturer, a generic and modular architecture for an open test environment is under development. A further goal of the Virtual and Hybrid Testing Next Generation (VHTNG) research project is to prepare a set of open standards for the interfaces to this architecture.
2017-09-19
Technical Paper
2017-01-2115
Gilberto Burgio, Leonardo Mangeruca, Alberto Ferrari, Marco Carloni, Virgilio Valdivia-Guerrero, Laura Albiol-Tendillo, Parithi Govindaraju, Marcel Gottschall, Olaf Oelsner, Sören Reglitz, Jann-Eve Stavesand, Andreas Himmler, Lionel Yapi
Abstract Multi-physics interactions between structural, electrical, thermal, or hydraulic components and the high level of system integration, characteristic of new aircraft designs, is increasing the complexity of both design and verification processes. Therefore the availability of tools, supporting integrated modelling, simulation, optimization and testing across all stages of aircraft design remains a critical challenge. This paper presents some results of the project MISSION (Modelling and Simulation Tools for Systems Integration on Aircraft). It is a collaborative task being developed under the European Union Clean Sky 2 Program, which is a public-private partnership bringing together aeronautics industrial leaders and public research organizations based in Europe. The first levels of integration of different models and tools proposed in the MISSION framework will be presented, along with simulation results.
2017-09-19
Technical Paper
2017-01-2086
Justin Lo
Abstract The fast growth of air traffic and the need for lighter and more fuel efficient aircraft is driving the ramp-up of important new aircraft programs. These increases in production rates are driving manufacturers to seek out robust and reliable installation systems. They must also adapt to the unique requirements of composite materials that now have an increasingly important place in the aerospace industry. Moreover, environmental constraints continue to evolve and drive new regulations, such as REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) in Europe. As an example, this regulation is leading to the adoption of non-chromate surface treatments and paints for most applications. The legacy generation of fasteners does not comply with all of these new requirements.
2017-09-19
Technical Paper
2017-01-2093
Thorsten Dillhoefer
Ever increasing process applications inspire us, as suppliers of aircraft, structural-assembly, and equipment to design innovative and modular, manufacturing cells in compliance with modern specification. The result is the new highly flexible Aerospace application specific robot identified as “POWER RACe”. This paper describes how benchmarks for flexible automated drilling and fastening are being achieved with the Power RACe technology platform.
2017-09-19
Technical Paper
2017-01-2096
Rainer Mueller, Matthias Vette, Aaron Geenen, Tobias Masiak
Abstract Assembly processes in aircraft production are difficult to automate due to technical risks. Examples of such technical challenges include small batch sizes and large product dimensions as well as limited work space for complex joining processes and organization of the assembly tasks. A fully automated system can be expensive and requires a large amount of programming knowledge. For these reasons, ZeMA believes a semi-automated approach is the most effective means of success for optimizing aircraft production. Many methods can be considered semi automation, one of which is Human-Robot-Collaboration. ZeMA will use the example of a riveting process to measure the advantages of Human-Robot-Collaboration systems in aircraft structure assembly. In the assembly of the aircraft aft section the pressure bulkhead is mounted with a barrel section using hundreds of rivets. This assembly process is a non-ergonomic and burdensome task in which two humans must work cooperatively.
2017-09-19
Technical Paper
2017-01-2059
Enrico Cestino, Giacomo Frulla, Renzo Duella, Paolo Piana, Francesco Pennella, Francesco Danzi
Abstract Future generations of civil aircrafts and unconventional unmanned configurations demand for innovative structural concepts to improve the structural performance, and thus reduce the structural weight, but also to allow possible material couplings to be made. Static and dynamic aeroelastic stability can be altered by these couplings. It is therefore necessary to use an accurate and computationally efficient beam model during the preliminary design phase. A stiffened box, made of isotropic material, but with the stiffeners oriented so that they originate the expected bending/torsion coupling, is considered in the present work. The overall equivalent bending, torsional and coupled stiffness is derived by means of homogenization of the shell skin and of the stiffener plate stiffness. A new equivalent homogeneous orthotropic material is determined and introduced into the equivalent plate configuration.
2017-09-19
Technical Paper
2017-01-2063
Patrick Browning, Bryan Shambaugh, Joseph Dygert
Abstract The dielectric barrier discharge (DBD) has been studied significantly in the past two decades for its applications to various aerodynamic problems. The most common aerodynamic applications have been stall/separation control and boundary layer modification. Recently several researchers have proposed utilizing the DBD in various configurations to act as viable propulsion systems for micro and nano aerial vehicles. The DBD produces stable atmospheric-pressure non-thermal plasma in a thin sheet with a preferred direction of flow. The plasma flow, driven by electrohydrodynamic body forces, entrains the quiescent air around it and thus develops into a low speed jet on the order of 10-1 to 101 m/s. Several researchers have utilized DBDs in an annular geometric setup as a propulsion device. Other researchers have used them to alter rectangular duct flows and directional jet devices. This study investigates 2-D duct flows for applications in micro plasma thrusters.
2017-09-19
Technical Paper
2017-01-2064
Parvez Alam M, Dinesh Manoharan, Satheesh Chandramohan, Sabarish Chakkath, Sunil MAURYA
Abstract In the present market, multiple sophisticate and expensive Thrust Test Rigs for Brushless Motors (BLDC Motor) are available making it impossible to conduct such thrust analysis on a regular and cost effective basis. Moreover the present test rigs are incapable to measure high Thrust values. This needs specialized thrust testing rig which is more expensive. This paper aims at Design & Development of the Small Scale Test Rig Setup for measurement of the thrust of any Brushless DC motor and helps in refining the Selection of motor and propeller. This is a set up based on cost efficiency factor to implement such rigs, test and for comparing the static thrust produced by the BLDC motor. The fairly simple construction contains a weighing machine, a Tachometer and a Wattmeter to measure the Thrust, RPM and the Current Drawn respectively, and provide comprehensive, accurate and efficient data coming from the BLDC Motor including the Propeller and Electronic Speed Control (ESC).
2017-09-19
Technical Paper
2017-01-2061
Andrea Cravana, Gerardo Manfreda, Enrico Cestino, Giacomo Frulla, Robert Carrese, Piergiovanni Marzocca
Abstract An accurate aeroelastic assessment of powered HALE aircraft is of paramount importance considering that their behaviour contrasts the one of conventional aircraft mainly due to the use of high aspect-ratio wings with distributed propulsion systems. This particular configuration shows strong dependency of the wing natural frequencies to the propulsion distribution and operating conditions. Numerical and experimental investigations are carried out to better understand the behaviour of flexible wings, focusing on the effect of distributed electric propulsion systems. Several configurations are investigated, including a single propulsion system using an engine pod (a weight with embedded electric motor, a propeller, and the wing-attached structure) installed at selected spanwise positions, and configurations with two and three propellers.
2017-09-19
Technical Paper
2017-01-2062
Tushar Choudhary, Mithilesh Sahu, Shreya KRISHNA
Abstract Gas turbine technology has traditionally been used by the aviation industry for powering the aircraft including acting as APU. Operational unmanned aerial vehicle (UAV) has a gas turbine which is used as Auxiliary Power Unit (APU) which generically have overall efficiency not exceeding 35% which limits the range in terms of time in the air for the same APU fuel carried onboard. Gas turbine exhaust heat energy is largely wasted and there is scope of its utilization by thermally coupling it with a solid-oxide fuel cell (SOFC). By coupling SOFC with the gas turbine (GT) based power system, a hybrid SOFC-GT based APU system has been proposed for thermodynamic analysis, and the thermal efficiency of the proposed system can be enhanced by 77%. This paper focuses on a thermodynamic cycle analysis of an internal reformed solid oxide fuel cell which is integrated with the gas turbine to form a hybrid APU system for an UAV.
2017-09-19
Technical Paper
2017-01-2065
Sebastian Bandycki, Michele Trancossi, Jose Pascoa
Abstract This paper presents a comparison between different hypotheses of propulsion of a spherical UAS. Different architectures have been analyzed assessing their specific aerodynamic, energetic, and flight mechanics features. The comparison has been performed assuming the robustness of flight control in different wind conditions, defining for each the specific operative ranges, mission profiles, and energy assessment. An effective energy assessment and comparison against a commercial UAS has been produced. Even if the paper considers a preliminary simplified configuration, it demonstrates clearly to be competitive against traditional quadcopters in a predefined reference mission.
2017-09-19
Technical Paper
2017-01-2070
Nicholas Anderson, Joseph Gao, Eric Whitman, Srikanth Gururajan
Abstract Recent advances in Small Unmanned Aerial Systems (SUAS) or drone technologies has resulted in their widespread use in a number of civilian applications, such as aerial imaging, infrastructure inspection, precision agriculture, among others. While this technology is accessible for everyone, it still requires a highly skilled operator to be able to successfully operate these drones in a safe and efficient manner. At the same time, developments in Virtual/Augmented Reality (V/AR) technologies present opportunities for combining the two into novel applications and use cases by providing an intuitive interface for interacting with the drones - opening up possibilities for safe and effective use of drones by relatively untrained operators.
2017-09-19
Technical Paper
2017-01-2073
Rick Calawa, Gavin Smith
Abstract The decision to replace a successful automated production system at the heart of a high volume aircraft factory does not come easily. A point is reached when upgrades and retrofits are insufficient to meet increasing capacity demands and additional floor space is simply unavailable. The goals of this project were to increase production volume, reduce floor space usage, improve the build process, and smooth factory flow without disrupting today’s manufacturing. Two decades of lessons learned were leveraged along with advancements in the aircraft assembly industry, modern machine control technologies, and maturing safety standards to justify the risk and expense of a ground-up redesign. This paper will describe how an automated wing spar fastening system that has performed well for 20 years is analyzed and ultimately replaced without disturbing the high manufacturing rate of a single aisle commercial aircraft program.
2017-09-19
Technical Paper
2017-01-2050
Piotr Synaszko, Michal Salacinski, Patryk Ciezak
Abstract The work concerns the selection of measurement parameters for selected non-destructive testing methods of Mi helicopter rotor blades after repair. Considered repair cases involve metal cracks in the sandwich skin and repair damage of honeycomb structure (puncture, dent). In the event of a crack, repair is performed by applying a composite-metal repair package. In case of damage of the core, its broken piece is replaced by a new one and then applied the same metal-composite package as in the case of crack repair. The present work focuses on detecting disbond between skin and core below repair patch and cracks under the repair package. Detecting cracks and assessing their length is important because the repair technology provides the repair package without removing of cracked part of skin. Authors have used laser shearography and C-scan methods for MIA and ET.
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