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Viewing 61 to 90 of 16536
2017-09-19
Technical Paper
2017-01-2123
Violet Leavers
The need to maintain aircraft in remote, harsh environments poses significant challenges for on-site condition monitoring. For example, in desert assignments or on-board ships, frequent rotation of staff with variable levels of skill requires condition monitoring equipment that is not only robust and portable but also user friendly and requiring a minimum of training to set up and use correctly. The mainstays of any on-site aerospace maintenance program are various fluid and particulate condition monitoring tests that convey information about the current mechanical state of the system. In the front line of these is the collection and analysis of wear debris particles retrieved from a component’s lubricating or power transmission fluid or from magnetic plugs. It is standard practice within the specialist laboratory environment to view and image wear debris using a microscope.
2017-09-19
Technical Paper
2017-01-2065
Sebastian Bandycki, Michele Trancossi, Jose Pascoa
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
2017-01-2101
Jon Barton Shields, Brian Peirce Barker
Abstract This paper discusses the merits, benefits and usage of autonomous key management (with implicit authentication) (AKM) solutions for securing Electronic Module to Electronic Module (i.e. ECUs, FCC, REUs, etc.) communication within air (and defense) vehicles and IoT applications; particularly for transmissions between externally exposed, edge Electronic Module sensors connected to Electronic Modules within the air (and defense) vehicle infrastructure. Specific benefits addressed include reductions of communication latency, implementation complexity, processing power and energy consumption. Implementation issues discussed include provisioning, key rotation, synchronization, re-synchronization, digital signatures and enabling high entropy.
2017-09-19
Journal Article
2017-01-2036
William Schley
Abstract Of all aircraft power and thermal loads, flight controls can be the most challenging to quantify because they are highly variable. Unlike constant or impulsive loads, actuator power demands more closely resemble random processes. Some inherent nonlinearities complicate this even further. Actuation power consumption and waste heat generation are both sensitive to input history. But control activity varies considerably with mission segment, turbulence and vehicle state. Flight control is a major power consumer at times, so quantifying power demand and waste heat is important for sizing power and thermal management system components. However, many designers sidestep the stochastic aspects of the problem initially, leading to overly conservative system sizing. The overdesign becomes apparent only after detailed flight simulations become available. These considerations are particularly relevant in trade studies comparing electric versus hydraulic actuation.
2017-09-19
Journal Article
2017-01-2114
Jann-Eve Stavesand, Sören Reglitz, Andreas Himmler
Abstract In the aerospace industry, methods for virtual testing cover an increasing range of test executions carried out during the development and test process of avionics systems. Over the last years, most companies have focused on questions regarding the evaluation and implementation of methods for virtual testing. However, it has become more and more important to seamlessly integrate virtual testing into the overall development process. For instance, a company’s test strategy might stipulate a combination of different methods, such as SIL and HIL simulation, in order to benefit from the advantages of both in the same test process. In this case, efforts concentrate on the optimization of the overall process, from test specification to test execution, as well as the test result evaluation and its alignment with methods for virtual testing.
2017-09-19
Technical Paper
2017-01-2126
Ashutosh Kumar Jha, Gaurav Sahay, Adishesha Sivaramasastry
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. Identifying and sensing right parameters at right time is the key for success of IVHM. It has opened up challenge to the sensor providers to make sensors smarter, self-contained to compute and communicate efficiently. The expected benefits of lesser time to maintenance, reduced operating cost and very busy airports are motivating aircraft manufacturers to come up with tools, techniques and technologies to enable advanced diagnostic and prognostic systems in aircrafts. These features not only enable detection of failures but also support prediction of tentative failures upfront based on historical data, trend analysis and estimating the future trends. At present, various groups are working on different systems and platforms for health monitoring of an aircraft e.g.
2017-09-19
Journal Article
2017-01-2142
Brandon Mahoney, Jamie Marshall, Thomas Black, Dennis Moxley
It is well recognized that weight savings within an airframe can result in significant lifetime cost savings and increased flight range. The transition of aluminum alloys to lighter, composite materials is an increasingly prevalent strategy to reduce weight on aircraft. This paper describes the application of a lightweight carbon fiber composite technology to aviation, engine start lithium batteries. The transition of lithium battery chassis technology from metal to composite introduces technical challenges not found with traditional battery chassis. Modern lithium batteries contain more than energy cells; common internal components include switch mode battery chargers, health and safety monitoring electronics, and even environmental control circuitry such as heaters. Consequently, electromagnetic interference disruption potential created by the electronics must be addressed.
2017-09-19
Journal Article
2017-01-2165
Christian Moeller, Hans Christian Schmidt, Philip Koch, Christian Boehlmann, Simon Kothe, Jörg Wollnack, Wolfgang Hintze
The high demand of efficient large scale machining operations by concurrently decreasing operating time and costs has led to an increasing usage of industrial robots in contrast to large scaled machining centers. The main disadvantage of industrial robots used for machining processes is their poor absolute accuracy, caused by the serial construction, resilience of gearings and sensitivity for temperature changes. Additionally high process forces that occur during machining of CFRP structures in aerospace industry lead to significant path errors due to low structural stiffness of the robot kinematic. These errors cannot be detected by means of motor encoders. That is why calibration processes and internal control laws have no effect on errors caused by elastic deformation. In this research paper an approach for increasing the absolute accuracy of an industrial milling robot with help of a laser tracker system during machining tasks will be presented.
2017-09-19
Technical Paper
2017-01-2159
Federico Cappuzzo, Olivier Broca, Jeremy Leboi
To answer the ever-increasing complexity of aircraft, it becomes of foremost importance to better and earlier assess the interactions among their systems and sub-systems. The study presents the Virtual Integrated Aircraft (VIA) methodology, which allows achieving the integration of aircraft systems with virtual means, complementing and preceding physical integration, which is usually completed at the end of the validation and integration phase. LMS Imagine.Lab platform provides the means for applying this methodology. A simulation architecture, integrating models from different platforms, is built and simulations are run on High Performance Computers (HPC) to cover multiple scenarios and therefore validate the selected architecture and pre-design in the early system development phases. Equipment, systems and subsystems are essential for the performance, safety, reliability and comfort.
2017-09-17
Technical Paper
2017-01-2514
Wei Han, Lu Xiong, Zhuoping Yu, Haocheng Li
Abstract BBW (Brake-by-wire) can increase the electric and hybrid vehicles performance and safety. This paper proposes a novel mechatronic booster system, which includes APS (active power source), PFE (pedal feel emulator), ECU (electronic control unit). The system is easily disturbed when the system parameters and the outside conditions change. The system performance is weakened. The cascade control technique can be used to solve the problem. This paper develops an adaptive cascade optimum control (ACOC) algorithm based on the novel mechatronic booster system. The system is divided into main loop and servo loop, both of them are closed-loop system. The servo-loop system can eliminate the disturbance which exists in the servo loop. So the robustness of the cascade control system is improved than which of the general closed-loop control system. Different control object is respectively chosen. The control-oriented mathematical model is designed.
2017-09-17
Technical Paper
2017-01-2500
Bo Huang, Wanyang Xia, Gangfeng Tan, Longjie Xiao, Zongsong Wang
Abstract Head-up Display (HUD) system can avoid drivers’ distraction on dashboard and effectively reduce collisions caused by emergency events, which is gradually being realized by researchers around the world. However, the current HUD only displays information like speed, fuel consumption, other information like acceleration and braking can’t be displayed yet. This research will use the indicator symbol‘s color and position change to remind drivers to brake or accelerate. Drivers can do driving operation timely and accurately. The system has the advantages of safety, intuition and real-time. The vehicle safe speed is calculated according to the road parameters, like adhesion coefficient and slope, and vehicle parameters, such as vehicle mass and centroid. Then, the appropriate braking operations are obtained by combining the vehicle driving state.
2017-09-04
Technical Paper
2017-24-0003
Andreas Sidorow, Vincent Berger, Ghita Elouazzani
Abstract Gasoline engines have typically a waste gate actuator to control the boost pressure. The electrification of the vehicle and combustion engine components leads to new challenges of application of electric actuators in engine components, like turbochargers, which are faced with relatively high ambient temperatures. Another challenge is a simulation and prediction of the mechanical load on the actuator and kinematic components at different application scenarios, which can help to find the optimal solution which fulfills the durability, controllability, etc. targets. This paper deals with a physical dynamic model of an electric waste-gate actuator and kinematic components. The modeling includes a thermal, electrical and mechanical parts of the turbocharger control system and is validated on test-bench and engine measurements including pulsation effects.
2017-09-04
Technical Paper
2017-24-0046
Richard Stone, Ben Williams, Paul Ewart
Abstract The increased efficiency and specific output with Gasoline Direct Injection (GDI) engines are well known, but so too are the higher levels of Particulate Matter emissions compared with Port Fuel Injection (PFI) engines. To minimise Particulate Matter emissions, then it is necessary to understand and control the mixture preparation process, and important insights into GDI engine mixture preparation and combustion can be obtained from optical access engines. Such data is also crucial for validating models that predict flows, sprays and air fuel ratio distributions. The purpose of this paper is to review a number of optical techniques; the interpretation of the results is engine specific so will not be covered here. Mie scattering can be used for semi-quantitative measurements of the fuel spray and this can be followed with Planar Laser Induced Fluorescence (PLIF) for determining the air fuel ratio and temperature distributions.
2017-09-04
Technical Paper
2017-24-0050
Anjan Rao Puttige, Robin Hamberg, Paul Linschoten, Goutham Reddy, Andreas Cronhjort, Ola Stenlaas
Abstract Improving turbocharger performance to increase engine efficiency has the potential to help meet current and upcoming exhaust legislation. One limiting factor is compressor surge, an air flow instability phenomenon capable of causing severe vibration and noise. To avoid surge, the turbocharger is operated with a safety margin (surge margin) which, as well as avoiding surge in steady state operation, unfortunately also lowers engine performance. This paper investigates the possibility of detecting compressor surge with a conventional engine knock sensor. It further recommends a surge detection algorithm based on their signals during transient engine operation. Three knock sensors were mounted on the turbocharger and placed along the axes of three dimensions of movement. The engine was operated in load steps starting from steady state. The steady state points of operation covered the vital parts of the engine speed and load range.
2017-09-04
Technical Paper
2017-24-0054
Francesco de Nola, Giovanni Giardiello, Alfredo Gimelli, Andrea Molteni, Massimiliano Muccillo, Roberto Picariello
Abstract In the last few years, the automotive industry had to face three main challenges: compliance with more severe pollutant emission limits, better engine performance in terms of torque and drivability and simultaneous demand for a significant reduction in fuel consumption. These conflicting goals have driven the evolution of automotive engines. In particular, the achievement of these mandatory aims, together with the increasingly stringent requirements for carbon dioxide reduction, led to the development of highly complex engine architectures needed to perform advanced operating strategies. Therefore, Variable Valve Actuation (VVA), Exhaust Gas Recirculation (EGR), Gasoline Direct Injection (GDI), turbocharging, powertrain hybridization and other solutions have gradually and widely been introduced into modern internal combustion engines, enhancing the possibilities of achieving the required goals.
2017-09-04
Technical Paper
2017-24-0068
Roberto Finesso, Ezio Spessa, Yixin Yang, Giuseppe Conte, Gennaro Merlino
Abstract A real-time approach has been developed and assessed to control BMEP (brake mean effective pressure) and MFB50 (crank angle at which 50% of fuel mass has burnt) in a Euro 6 1.6L GM diesel engine. The approach is based on the use of feed-forward ANNs (artificial neural networks), which have been trained using virtual tests simulated by a previously developed low-throughput physical engine model. The latter is capable of predicting the heat release and the in-cylinder pressure, as well as the related metrics (MFB50, IMEP - indicated mean effective pressure) on the basis of an improved version of the accumulated fuel mass approach. BMEP is obtained from IMEP taking into account friction losses. The low-throughput physical model does not require high calibration effort and is also suitable for control-oriented applications.
2017-09-04
Technical Paper
2017-24-0069
Hyunwook Park, Jugon Shin, Choongsik Bae
Abstract The spray and combustion of diesel fuel were investigated to provide a better understanding of the evaporation and combustion process under the simulated cold-start condition of a diesel engine. The experiment was conducted in a constant volume combustion chamber and the engine cranking period was selected as the target ambient condition. Mie scattering and shadowgraph techniques were used to visualize the liquid- and vapor-phase of the fuel under evaporating non-combustion conditions (oxygen concentration=0%). In-chamber pressure and direct flame visualization were acquired for spray combustion conditions (oxygen concentration=21%). The fuel was injected at an injection pressure of 30 MPa, which is the typical pressure during the cranking period.
2017-09-04
Technical Paper
2017-24-0126
Christian Zöllner, Dieter Brueggemann
Abstract The removal of particulate matter (PM) from diesel exhaust is necessary to protect the environment and human health. To meet the strict emission standards for diesel engines an additional exhaust aftertreatment system is essential. Diesel particulate filters (DPF) are established devices to remove emitted PM from diesel exhaust. But the deposition and the accumulation of soot in the DPF influence the filter back pressure and therefore the engine performance and the fuel consumption. Thus a periodical regeneration through PM oxidation is necessary. The oxidation behavior should result in an effective regeneration mode that minimizes the fuel penalty and limits the temperature rise while maintaining a high regeneration efficiency. Excessive and fast regenerations have to be avoided as well as uncontrolled oxidations, which may lead to damages of the filter and fuel penalty.
2017-09-04
Technical Paper
2017-24-0130
Antonio Paolo Carlucci, Marco Benegiamo, Sergio Camporeale, Daniela Ingrosso
Abstract 1 Nowadays, In-Cylinder Pressure Sensors (ICPS) have become a mainstream technology that promises to change the way the engine control is performed. Among all the possible applications, the prediction of raw (engine-out) NOX emissions would allow to eliminate the NOX sensor currently used to manage the after-treatment systems. In the current study, a semi-physical model already existing in literature for the prediction of engine-out nitric oxide emissions based on in-cylinder pressure measurement has been improved; in particular, the main focus has been to improve nitric oxide prediction accuracy when injection timing is varied. The main modification introduced in the model lies in taking into account the turbulence induced by fuel spray and enhanced by in-cylinder bulk motion.
2017-09-04
Technical Paper
2017-24-0137
Zhen Zhang, Luigi del Re, Richard Fuerhapter
Abstract During transients, engines tend to produce substantially higher peak emissions like soot - the main fraction of particular matter (PM) - which are the longer the more important as the steady state emissions are better controlled. While Diesel particulate filters are normally able to block them, preventing their occurrence would of course be more important. In order to achieve this goal, however, they must be measurable. While for most emissions commercial sensors of sufficient speed and performance are available, the same is not true for PMs, especially for production engines. Against this background, in the last years the possible use of a full stream 50Hz sensor based on Laser Induced Incandescence (LII) was investigated, and the results were very encouraging, showing that the sensor could recognize transient changes undetected by conventional measurement systems (like the AVL Opacimeter) but confirmed by the analysis of combustion.
2017-09-04
Technical Paper
2017-24-0153
Sergey Shcherbanev, Alexandre De Martino, Andrey Khomenko, Svetlana Starikovskaia, Srinivas Padala, Yuji Ikeda
Abstract Requirements for reducing consumption of hydrocarbon fuels, as well as reducing emissions force the scientific community to develop new ignition systems. One of possible solutions is an extension of the lean ignition limit of stable combustion. With the decrease of the stoichiometry of combustible mixture the minimal size of the ignition kernel (necessary for development of combustion) increases. Therefore, it is necessary to use some special techniques to extend the ignition kernel region. Pulsed microwave discharge allows the formation of the ignition kernels of larger diameters. Although the microwave discharge igniter (MDI) was already tested for initiation of combustion and demonstrated quite promising results, the parameters of plasma was not yet studied before. Present work demonstrates the results of the dynamics of spatial structure of the MDI plasma with nanosecond time resolution.
2017-09-04
Journal Article
2017-24-0051
Ferdinando Taglialatela, Mario Lavorgna, Silvana Di Iorio, Ezio Mancaruso, Bianca Maria Vaglieco
Abstract In order to meet the increasingly strict emission regulations, several solutions for NOx and PM emissions reduction have been studied. Exhaust gas recirculation (EGR) technology has become one of the more used methods to accomplish the NOx emissions reduction. However, actual control strategies do not consider, in the definition of optimal EGR, its effect on particle size and density. These latter have a great importance both for the optimal functioning of after-treatment systems, but also for the adverse effects that small particles have on human health. Epidemiological studies, in fact, highlighted that the toxicity of particulate particles increases as the particle size decreases. The aim of this paper is to present a Neural Network model able to provide real time information about the characteristics of exhaust particles emitted by a Diesel engine.
2017-09-04
Journal Article
2017-24-0109
Nic Van Vuuren, Lucio Postrioti, Gabriele Brizi, Federico Picchiotti
Selective Catalytic Reduction (SCR) diesel exhaust aftertreatment systems are virtually indispensable to meet NOx emissions limits worldwide. These systems generate the NH3 reductant by injecting aqueous urea solution (AUS-32/AdBlue®/DEF) into the exhaust for the SCR NOx reduction reactions. Understanding the AUS-32 injector spray performance is critical to proper optimization of the SCR system. Specifically, better knowledge is required of urea sprays under operating conditions including those where fluid temperatures exceed the atmospheric fluid boiling point. Results were previously presented from imaging of an AUS-32 injector spray which showed substantial structural differences in the spray between room temperature fluid conditions, and conditions where the fluid temperature approached and exceeded 104° C and “flash boiling” of the fluid was initiated.
2017-09-04
Journal Article
2017-24-0140
Roberto Aliandro Varella, Gonçalo Duarte, Patricia Baptista, Pablo Mendoza Villafuerte, Luis Sousa
Abstract Due to the need to properly quantify vehicle emissions in real world operation, Real Driving Emissions (RDE) test procedures will be used for measuring gaseous emissions on new EURO 6 vehicles.at the RDE 1 & 2: Commission Regulation (EU) 2016/427 of 10 March 2016 amending Regulation (EC) No 692/2008 as regards emissions from light passenger and commercial vehicles. Updated regulations have been enhanced to define RDE tests boundaries and data analysis procedures, in order to provide an accurate way to obtain representative results. The boundary conditions defined for vehicle testing include external atmospheric temperature, which can range from 0°C to around 30°C, for moderate conditions and -7°C up to 35°C for extended conditions in RDE tests. As a result of this range of possible test ambient temperature, pollutant emissions and energy consumption can vary considerably.
2017-09-04
Journal Article
2017-24-0045
Blane Scott, Christopher Willman, Ben Williams, Paul Ewart, Richard Stone, David Richardson
Abstract In-cylinder temperature measurements are vital for the validation of gasoline engine modelling and useful in their own right for explaining differences in engine performance. The underlying chemical reactions in combustion are highly sensitive to temperature and affect emissions of both NOx and particulate matter. The two techniques described here are complementary, and can be used for insights into the quality of mixture preparation by measurement of the in-cylinder temperature distribution during the compression stroke. The influence of fuel composition on in-cylinder mixture temperatures can also be resolved. Laser Induced Grating Spectroscopy (LIGS) provides point temperature measurements with a pressure dependent precision in the range 0.1 to 1.0 % when the gas composition is well characterized and homogeneous; as the pressure increases the precision improves.
2017-08-25
Technical Paper
2017-01-1945
Dr. Raimund Varnhagen
eHorizon (for electronic horizon) integrates topographical and digital map data with sensor data, namely GPS receivers, for predictive control of vehicle systems. The eHorizon solution constantly sends small data packages via the vehicles data network (CAN bus). These packages contain information about the stretch of road ahead as well as topographic information. With this information, the engine control unit, the transmission control device or the driver assistance systems can optimize their respective functions. When eHorizon is used in commercial vehicles a significant reduction in fuel consumption has been proven with several commercial vehicles OEs. The eHorizon has numerous possible applications. Based upon eHorizon's digital map data, the stretch of road ahead and its topography can be integrated in the strategy of the engine management. It is possible to reduce fuel consumption in various driving situations.
2017-08-01
Journal Article
2017-01-9283
Peter R. Hooper
Abstract This paper reports on the research and development challenges experienced from dynamometer testing of a spark ignition UAV engine operating on heavy fuel. The engine is a segregated scavenging two stroke engine with air charge delivery by means of integral stepped pistons overcoming durability issues of conventional crankcase scavenged engines. A key element of the experimental study builds upon performance development to address the need for repeatable cold start on low volatility fuel thereby eliminating gasoline from UAV theatres of deployment. Lubrication challenges normally associated with crankcase scavenged two stroke engines are avoided by the integrated re-circulatory lubrication system. The fuel explored in this study is kerosene JET A-1.
2017-07-10
Technical Paper
2017-28-1935
Vellavedu Velumani Praveen, P Baskara Sethupathi
Abstract Formula SAE is a prestigious engineering design competition, where student team design, fabricate and test their formula style race car, with the guidelines of the FSAE rulebook, according to which the car is designed, for example the engine must be a four-stroke, Otto-cycle piston engine with a displacement no greater than 710cc. According to FSAE 2017 Rule Book [1], ARTICLE 3, IC3.2 and IC3.3 state that the maximum sound level should not exceed 110 dBC at an average piston speed of 15:25 m/s (for the KTM 390 engine, which has 60 mm stroke length, the noise level will be measured at 7500 RPM) and 103 dBC at Idle RPM. So, the active muffler which works as a normal reflective muffler till the 7500 RPM range, after which an electronic controlled throttle mechanism is used to reduce the backpressure (since after 7500 RPM the noise level doesn't matter in FSAE) by using tach signal from the engine to control the throttle (two position).
2017-07-10
Technical Paper
2017-28-1969
Senthil Ram Nagapillai Durairaj, Thulasirajan Ganesan, Praveen Chakrapani Rao
Abstract Magnesium alloy current being used for automotive sector and are being significantly used for manufacturing engine block as offering higher power to weight ratio to the vehicle. In this context, the magnesium alloy has been used in the replacement of aluminium alloy for the starter housing which in turn increase the power to weight ratio of the motor. Considering the operation condition of starter motor in the engine of the vehicles, the starter motor is being exposed to the harsh environment, where its system is being tested for Noise, Vibration and Harshness. In this paper, the magnesium alloy housing is used to study the vibration and noise developed in the starter motor and the same is compared with the noise and vibration of the motor when it being used with Aluminium alloy Housing. First, the vibration study is carried out for the housing part alone to capture the resonant frequency of the both housing alloy say, Aluminium and Magnesium.
2017-07-10
Technical Paper
2017-28-1967
Senthil Ram Nagapillai Durairaj, Thulasirajan Ganesan, Praveen Chakrapani Rao
Abstract Global Automotive Industry is mandated with the task of emission reduction and mileage improvements. One of the key areas being looked at from mileage standpoint is light weighting. While Aluminum body is replacing Steel is many vehicular applications, in Starter Motor Aluminum is the key component. Therefore, any attempt at light weighting must consider Aluminum. A Starter motor fits directly on to the engine. Aluminum being the housing material provides structural stability. It also performs the role of heat dissipation being a good thermal conductor and source of electrical ground path. Aluminum constitutes 20 - 25% of Starter motor weight. Any significant weight reduction cannot be achieved unless we look at the components made of Aluminum, namely die cast Housing and End plate. The alternatives considered in this study include engineered plastics, magnesium alloy and composites.
Viewing 61 to 90 of 16536