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Viewing 121 to 150 of 382
2015-06-15
Technical Paper
2015-01-2158
Tatsuma Hyugaji, Shigeo Kimura, Haruka Endo, Mitsugu Hasegawa, Hirotaka Sakaue, Katsuaki Morita, Yoichi Yamagishi, Nadine Rehfeld, Benoit Berton, Francesc Diaz, Tarou Tanaka
Coating has been recently considered as having good potential for use in preventing in-cloud icing on the leading edge of the lifting surfaces of an aircraft in cold climates. In terms of wettability, a coat may exhibit hydrophobicity or hydrophilicity depending on its specific properties. The same applies to the ice adhesion strength, which may be either high or low. It is thus necessary to determine which type of anti-icing or de-icing coat would be appropriate for a particular application in order to fully utilize its specific properties. Notwithstanding, a coat is incapable of preventing ice accretion by itself, and a perfect icephobic coat is yet to be developed. Coating is also sometimes applied to the surfaces of electrical heaters and load-applying machines to enable them to function more effectively and use less energy. The coating used for an electric heater, for instance, should be hydrophobic because of the need for rapid removal of molten water from the surface.
2015-06-15
Technical Paper
2015-01-2135
Martin Schulz, Michael Sinapius
Abstract A designer of a new mechanical ice protection system for airplanes needs to know how much and in which way he has to deform the surface to break off the ice. The ice adhesion strength is often used as a design value. Several methods have been published to measure the adhesive strength of ice. This paper analyzes the interface stresses created by those methods and discusses the way the adhesion strength is derived. A finite element method tool is used to provide insight into the stress state for different load cases. The implication of these illustrations is that equations which use only ultimate force and total interfacial area to calculate adhesion strength miss local stress concentrations and crack nucleation. Hence, the derived adhesion strength may not be comparable within different testing methods, because each testing procedure neglects different parameters like specimen size, substrate thickness and stiffness.
2015-06-15
Technical Paper
2015-01-2078
Alric Rothmayer, Hui Hu
Abstract A strong air/water interaction theory is used to develop a fast simplified model for the trapping of water in a film that flows over sub-grid surface roughness. The sub-grid model is used to compute correction factors that can alter mass transport within the film. The sub-grid model is integrated into a covariant film mass transport model of film flow past three-dimensional surfaces in a form that is suitable for use in aircraft icing codes. Sample calculations are presented to illustrate the application of the model.
2015-06-15
Technical Paper
2015-01-2076
Caroline Laforte, Neal Wesley, Marc Mario Tremblay
Abstract This study presents a new method to evaluate and compare the anti-icing performance, i.e., the ability to delay the reformation of ice, of runways and taxiways deicing/anti-icing fluids (RDF) under icing precipitation, based on the skid resistance values, obtained with the Portable Skid Resistance Tester (PSRT). In summary, the test consists of applying, on a standardized concrete pavement sample, a given quantity of de-icing fluid. Following this application, the concrete sample is submitted to low freezing drizzle intensities, in a cold chamber at −5.0 ± 0.3°C. The skid resistance of concrete is measured at 5 minute intervals, until the concrete becomes completely iced. The anti-icing performance of 5 different fluids, both experimental and commercial, was assessed in comparison with a reference solution of 50% w/w K-formate. The anti-icing performance is analyzed based on two parameters: the duration (Icing Protection Time, IPT) and the effectiveness of this protection.
2015-06-15
Technical Paper
2015-01-2149
Caroline Laforte, Caroline Blackburn, Jean Perron
Abstract This paper depicts icephobic coating performances of 274 different coatings, including 11 grease-type coatings, which were tested over the past 10 years in various research projects at the Anti-Icing Materials International Laboratory (AMIL). Icephobic performance is evaluated using two comparative test methods. The first method, the ice Centrifuge Adhesion Test (CAT), measures the force required to separate the accreted ice from the coating (e.g. adhesive failure). The test involves simultaneously icing, under supercooled precipitation, the extremity of bare reference and freshly coated aluminum samples. The ice adhesion shear stress is calculated from the ice detachment rotation speed. The results are reported as Adhesion Reduction Factor (ARF), which is the ice adhesion stress on the bare aluminum reference samples divided by the ice adhesion stress on the coated samples.
2015-06-15
Technical Paper
2015-01-2157
Mengyao Leng, Shinan Chang, Yuanyuan Zhao
Abstract Aircraft icing causes a great threaten to flight safety. With the development of anti-icing or de-icing systems for aircraft, some attention has been paid on coating strategies for an efficient way to prevent water remaining on the surface. By application of hydrophobic or super-hydrophobic coatings, characterized by low surface adhesion, shedding of liquid from the surface can be enhanced. The motivation behind this work is to identify the way that wettability affects the motion of runback water, and establish an empirical formula of critical departure diameter. The surface property is characterized by the equilibrium contact angle and the hysteresis angle. The relationship between the air speed and the droplet shedding diameter is studied, corresponding to different surfaces.
2015-04-14
Journal Article
2015-01-0441
Takashi Takiguchi, Yusuke Yano, Yasuhiro Takii, Nobuyuki Ohta
Abstract With demands for enhanced environmental performance such as fuel economy, the tendency has been to reduce the amount of wind introduced to the engine room to reduce drag. Meanwhile, exhaust gas temperatures are increasing in order to reduce emissions concentrations. As a result, the temperature environments for parts inside the engine room and underfloor parts are becoming harsher, and accurately understanding the temperature environments of parts is crucial in determining Engine room component layout during vehicle development and applying effective thermal countermeasures. Computational fluid dynamics (CFD) are effective for understanding complex phenomena such as heat generation and cooling. However, this paper reports the development of a method for accurately calculating the vehicle temperature distribution through identification from test results.
2015-04-14
Technical Paper
2015-01-0439
Daniel B. Kosinski
Abstract The current reliability growth planning model used by the US Army, the Planning Model for Projection Methodology (PM2), is insufficient for the needs of the Army. This paper will detail the limitations of PM2 that cause Army programs to develop reliability growth plans that incorporate unrealistic assumptions and often demand that infeasible levels of reliability be achieved. In addition to this, another reliability growth planning model being developed to address some of these limitations, the Bayesian Continuous Planning Model (BCPM), will be discussed along with its own limitations. This paper will also cover a third reliability growth planning model that is being developed which incorporates the advantageous features of PM2 and BCPM but replaces the unrealistic assumptions with more realistic and customizable ones.
2015-04-14
Technical Paper
2015-01-0486
Jamshid Mohammadi, Mehdi Modares
Abstract Performance data offers a powerful tool for system condition assessment and health monitoring. In most applications, a host of various types of sensors is employed and data on key parameters (describing the system performance) is compiled for further analysis and evaluation. In ensuring the adequacy of the data acquisition process, two important questions arise: (1) is the complied data robust and reasonable in representing the system parameters; and (2) is the duration of data acquisition adequate to capture a favorable percentage (say for example 90%) of the critical values of a given system parameter? The issue related to the robustness and reasonableness of data can be addressed through known values for key parameters of the system. This is the information that is not often available.
2015-04-14
Technical Paper
2015-01-0487
Lev Klyatis
Abstract This paper will discuss the problem with successful predicting of product performance (reliability, quality, durability, safety, recalls, profit, life cycle cost, and other interconnected technical and economic components of performance). The best component for analysing the performance situation during service life, including predicting, is recalls, because, first, recall accumulates the safety, reliability, durability, quality, profit, and total economic situation. And second, there is open official and objective information about the number of recalls from Government (National Highway Trafic Safety Administration and others), as well as companies-producers. Therefore, for analyzing the situation with the product performance, including predicting, this paper considers the situation with recalls.
2015-04-14
Technical Paper
2015-01-0204
Biswajit Panja, Lars Wolleschensky
Abstract In this paper we propose a secure wireless sensor network system for vehicle health monitoring (VHM). We discuss the architecture of the proposed model, and it's implementation in vehicles. Modified AES-CCM is used to provide confidentiality in the network. In the proposed scheme combination of interactive and non-interactive methods are used for reliable message delivery.
2015-04-14
Journal Article
2015-01-0206
Jihas Khan
Abstract Security access feature based on seed-key mechanism is widely used in automotive electronics, mainly for flashing ECU software, writing or reading specific parameter values and running diagnostic routines. There exist a number of techniques to decode the algorithm for key generation from a specific seed. Such techniques can put vehicle network at great risks due to an intruder flashing unauthorized version of ECU software, or changing internal parameters of ECU, or changing a VIN number. A lot more similar malicious attacks can be done by getting control over the ECUs. Attackers can exploit this vulnerability to alter the performance from the stock and affect the safety of the passengers. A novel and fool proof algorithm to protect the vehicle and ECU from such malicious attacks is explained in this paper. An advanced encryption technique is developed and tested in ECU to replace the current seed-key mechanisms for ECU security guarantying a secure operation of the vehicle.
2015-04-14
Technical Paper
2015-01-0267
Ryoichi Inada, Teppei Hirotsu, Yasushi Morita, Takahiro Hata
Abstract The ISO 26262 is a functional safety standard for road vehicles. The standard requires manufacturers to conduct quantitative assessment of the diagnostic coverage (DC) of products. The DC is defined as the percentage of failure probability covered by safety mechanisms. However, DC evaluation methods for drift faults, in which the change in element values is not constant, have not been discussed. In this paper, we propose a DC evaluation method for analog circuits with drift faults. With this method, we first parameterize the effect of drift faults onto a bounded region then split the region into safe fault, hazardous detectable fault, and hazardous undetectable fault regions. We evaluate the classification rate distribution by the area ratios of these regions.
2015-04-14
Technical Paper
2015-01-0498
Matt Gynn, Jamie Steele
Abstract This study explores the process changes and challenges encountered during the transition from physical to virtual automotive maintenance and service operations. The confirmation process was reworked significantly, while the final evaluation and reporting process was able to be maintained. Problems were encountered with the organization of the digital part data, the increase in workload of virtual simulations over physical checks, and the limitations of current simulation and virtual reality (VR) technologies. Ideas for future enhancements of product lifecycle management (PLM) and simulation systems are explored.
2015-04-14
Technical Paper
2015-01-0494
Sulki Seong, Wangoo Kim, Daesung Bae, Seungpyo Lee, Younggeol Cho, Kyeongdeok Yang
Abstract A rotating bearing must have an excellent durability life. Various studies have been conducted for a long time to predict the bearing durability life. However, the bearing durability life has been predicted by an analytic formula in terms of the raceway and ball. A finite element structural analysis has been carried out for a flange, commonly with an assumption of a static load. So it is difficult to consider the dynamic effects (Centrifugal force, Gyroscope effect) of the bearing, which is very important due to its high speed operation. In order to predict the accurate bearing durability life, the dynamic effects must be considered. This paper proposes a method for bearing durability life prediction, considering dynamic effects. Contact between the raceway and ball is one of the important factors to take into account for the dynamic effects of the bearing.
2015-04-14
Technical Paper
2015-01-1405
Guanjun Zhang, Feng Yu, Zhigao OuYang, Huiqin Chen, Zhonghao Bai, Libo Cao
Abstract The combination of passive and active vehicle safety technologies can effectively improve vehicle safety. Most of them predict vehicle crashes using radar or video, but they can't be applied extensively currently due to the high cost. Another collision forecasting method is more economic which is based on the driver behavior and vehicle status, such as the acceleration, angular velocity of the brake pedal and so on. However, the acceleration and angular velocity of the brake pedal will change with the driver and the vehicle type. In order to study the effect of different drivers and vehicle types on the braking acceleration and angular velocity of the brake pedal, six volunteers were asked to drive five vehicles for simulating the working conditions of emergency braking, normal braking, inching braking and passing barricades under different velocities. All the tests were conducted on asphalt road, and comprehensive experimental design was used to arrange tests.
2015-04-14
Journal Article
2015-01-0918
Daniel Duke, Andrew Swantek, Alan Kastengren, Kamel Fezzaa, Christopher Powell
Abstract Cavitation plays an important role in fuel injection systems. It alters the nozzle's internal flow structure and discharge coefficient, and also contributes to injector wear. Quantitatively measuring and mapping the cavitation vapor distribution in a fuel injector is difficult, as cavitation occurs on very short time and length scales. Optical measurements of transparent model nozzles can indicate the morphology of large-scale cavitation, but are generally limited by the substantial amount of scattering that occurs between vapor and liquid phases. These limitations can be overcome with x-ray diagnostics, as x-rays refract, scatter and absorb much more weakly from phase interfaces. Here, we present an overview of some recent developments in quantitative x-ray diagnostics for cavitating flows. Measurements were conducted at the Advanced Photon Source at Argonne National Laboratory, using a submerged plastic test nozzle.
2015-04-14
Technical Paper
2015-01-0926
Tianyun Li, Min Xu, David Hung, Shengqi Wu, Siqi Cheng
Abstract Comparing with port-fuel-injection (PFI) engine, the fuel sprays in spark-ignition direct-injection (SIDI) engines play more important roles since they significantly influence the combustion stability, engine efficiency as well as emission formations. In order to design higher efficiency and cleaner engines, further research is needed to understand and optimize the fuel spray atomization and vaporization. This paper investigates the atomization and evaporation of n-pentane, gasoline and surrogate fuels sprays under realistic SIDI engine conditions. An optical diagnostic technique combining high-speed Mie scattering and Schlieren imaging has been applied to study the characteristics of liquid and vapor phases inside a constant volume chamber under various operating conditions. The effects of ambient temperature, fuel temperature, and fuel type on spray atomization and vaporization are analyzed by quantitative comparisons of spray characteristics.
2015-04-14
Technical Paper
2015-01-0881
Sunyu Tong, Haimiao Li, Zhaohui Yang, Jun Deng, Zongjie Hu, Liguang Li
Abstract An ion current sensor is employed in a 4 cylinder production SI engine for combustion diagnosis during combustion process, knock, and low speed pre-ignition (LSPI) detection. The results show that the ion current peak value and ion current peak phase have strong correlation with the cylinder pressure and pressure peak phase respectively. The COV of ion current integral value is greater than the COV of IMEP at the same operating condition. Results show that the ion current signal is sensitive to different lambdas. Using ion current signal, the knock in any given cylinder can be detected. Importantly, the ion sensor successfully detected the low speed pre-ignition (LSPI) about more than 20 °CA before spark ignition.
2015-04-14
Technical Paper
2015-01-1249
Jinli Wang, Fuyuan Yang, Minggao Ouyang
Abstract There is increasing demand for engine diagnostic and control with in-cylinder pressure signal. However, the application of cylinder pressure sensors are restricted by the high cost of the sensor. Another possible way for engine combustion state estimation is by processing of instantaneous crankshaft speed signal, but it is limited by the precision and complexity of the algorithm. It could be a solution by processing one cylinder pressure signal in combination with a crankshaft speed signal. The indicated torque could be estimated through engine speed processing and also from the measure cylinder pressure for the reference cylinder. Measurement results from experiments show that the indicated torque error traces of different cylinder are similar in shape. According to this assumption, the reference cylinder with cylinder pressure signal available can serve as both a parameter calibration information source and an error reduction measure.
2015-01-14
Journal Article
2015-26-0090
Federico Stola, Matteo De Cesare, Luca Lacchini, Nicolò Cavina, Sandeep Sohal
Abstract The Selective Catalytic Reduction (SCR) system installed on the exhaust line is currently widely used on Diesel heavy-duty trucks and it is considered a promising technique for light and medium duty trucks, large passenger cars and off-highway vehicles, to fulfill future emission legislation. Some vehicles of these last categories, equipped with SCR, have been already put on the market, not only in the US, where the emission legislation on Diesel vehicles is more restrictive, but also in Europe, demonstrating to be already compliant with the upcoming Euro 6. Moreover, new and more stringent emission regulations and homologation cycles are being proposed all over the world, with a consequent rapidly increasing interest for this technology. As a matter of fact, a physical model of the Diesel Exhaust Fluid (DEF) supply system is very useful, not only during the product development phase, but also for the implementation of the on-board real-time controller.
2015-01-14
Technical Paper
2015-26-0239
Azeez Ahmed, Gopalakrishna Deshpande, Varghese Manu Varghese, Ramakrishnan Rangaswamy, Prakash Prashanth Ravi
Abstract The engine research and development has a significant contribution to meet the stringent emission norms and the changing global market demands. Leveraging the available virtual engineering methods to improve performance, velocity, quality and diminish the lead time is the key for any global brand to stay in the competition. It is the key element to reduce the research and development costs substantially by virtually developing the idea as it is conceived. Engine development test cells consist of expensive test and measurement systems which demand skilled labor and advanced equipment. Effective utilization of the test cells is essential to meet the scheduled project deadlines and cost targets. Engine Design process and tools when used effectively can increase the efficiency and lower the test cell operation costs substantially. This paper discusses the examples for this application in the area of engine installation, sensitive instrumentation/assembly.
2015-01-14
Technical Paper
2015-26-0043
Rajesh Kashyap, Vamsidhar Sunkari, Prakash Verma
Abstract Regular service of the vehicle is to be done with high precision service equipment, to ensure the factory performance of the vehicle over the entire life of product usage. However, complex nature of the physical processes involved in the service of the vehicle subsystems makes it costly for optimizing the service equipment performance for entire range of operation. Air-conditioning service (ACS) equipment is one such product in the diagnostics domain which deals with compressible, transient and two phase flow in open loop systems. Development of control system for the service equipment to perform optimally over the entire operational range requires accurate mathematical model of the system under study. Application of mathematical model based approach requires calculation of geometrical details, environment information and fluid properties during the process for estimating the process behavior.
2015-01-14
Technical Paper
2015-26-0013
Ashwini S. Athreya, Sreenath K R, Deepak Sharma
Abstract In the era where governmental agencies are perennially pushing automobile OEMs for reducing harmful emissions and customers looking for vehicles with better fuel economy values, it is imperative on the manufacturers to implement new technologies to appease them. Of the many new technologies, the most promising ones are the new control strategies/algorithms which predictively access the road condition, weather, traffic situations and help automobile to function in the most efficient mode. These control strategies/algorithms are termed as “Predictive technologies”. The most common way to assess the benefit of such new technologies is to simulate the vehicle behavior in conjunction with the existing complex control strategies of Hybrid vehicles in simulation environment.
2014-11-11
Journal Article
2014-32-0009
Alexander Trattner, Helmut Grassberger, Oliver Schoegl, Stephan Schmidt, Roland Kirchberger, Helmut Eichlseder, Armin Kölmel, Stephan Meyer, Tim Gegg
Abstract One of the most significant current discussions worldwide is the anthropogenic climate change accompanying fossil fuel consumption. Sustainable development in all fields of combustion engines is required with the principal objective to enhance efficiency. This certainly concerns the field of hand-held power tools as well. Today, two-stroke SI engines equipped with a carburetor are the most widely used propulsion technology in hand-held power tools like chain saws and grass trimmers. To date, research tended to focus on two-stroke engines with rich mixture setting. In this paper the advantages and challenges of leaner and/or lean operation are discussed. Experimental investigations regarding the influence of equivalence ratio on emissions, fuel consumption and power have been performed. Accompanying 3D-CFD simulations support the experiments in order to gain insight into these complex processes. The investigations concentrate on two different mixture formation processes, i.e.
2014-11-11
Technical Paper
2014-32-0036
Jan Czerwinski, Markus Kurzwart, Andreas Mayer, Pierre Comte
Abstract The progressing exhaust gas legislation for on- and off-road vehicles includes gradually the nanoparticle count limits. The invisible nanoparticles from different emission sources penetrate like a gas into the living organisms and may cause several health hazards. The present paper shows some results of a modern chain saw with & without oxidation catalyst, with Alkylate fuel and with different lube oils. The measurements focused specially on particulate emissions. Particulates were analysed by means of gravimetry (PM) and granulometry SMPS (PN). In this way the reduction potentials with application of the best materials (fuel, lube oil, ox-cat.) were indicated. It has been shown that the particle mass (PM) and the particle numbers (PN), which both consisting almost exclusively of unburned lube-oil, can attain quite high values, but can be influenced by the lube oil quality and can be considerably reduced with an oxidation catalyst.
2014-11-11
Technical Paper
2014-32-0115
Mikael Bergman, Magnus Bergwall, Thomas Elm, Sascha Louring, Lars Nielsen
Abstract Present two stroke engines used for hand held power tools must confirm to prevailing emission legislation. A fact is that today the engines have to be run at leaner air fuel setting resulting in less amount of lubrication oil passing through the engine. This lean mixture combined with high mixture trapping efficiency also affects the combustion, raising the overall working temperature of the engine. So to gain more robustness out of these air-cooled power heads one viable route is to use different coatings to take control of tribology and heat management within the two stroke power head. In this paper a first discussion and description of the different coatings and their merits to the air cooled two stroke engine is conducted. Furthermore engine data for the test engine, in this case a 70cc professional chainsaw are presented. The outcome of engine dyno testing of the different coatings are presented and analyzed for further discussion.
2014-11-11
Technical Paper
2014-32-0111
Brian Mason, Keith Lawes
Abstract For handheld power tools, a four-stroke engine allows compliance with exhaust emissions regulations although four-stroke engines available tend to have unfavorable power to weight. The requirement for a low cost diecast block compromises valve sizes and port flow. While dynamic valve train limitations restrict maximum engine speeds. The use of a rotary valve as opposed to poppet valves avoids these issues and results in an engine with competitive performance. The engine block can be diecast and the engine can operate up to 14,000 rpm without valve related issues. This paper describes the evolution of a rotary valve concept and its application to two 35cc handheld development engines. The HRCV35 is based on a belt driven rotary valve horizontally mounted parallel to the crankshaft axis. The VRCV35 is based on a gear driven rotary valve vertically mounted on the cylinder axis. In both configurations, the rotary valve exposes inlet and exhaust ports providing unrestricted flow.
2014-10-13
Technical Paper
2014-01-2589
Chunshan Li, Guoying Chen, Changfu Zong
Abstract The passive fault-tolerant approach for four-wheel independently driven and steered (4WID/4WIS) electric vehicles has been investigated in this study. An adaptive control based passive fault-tolerant controller is designed to improve vehicle safety, performance and maneuverability when an actuator fault happens. The proposed fault tolerant control method consists of the following three parts: 1) a fault detection and diagnosis (FDD) module that monitors vehicle driving condition, detects and diagnoses actuator failures with the inequality constraints; 2) a motion controller that computes the generalized forces/moments to track the desired vehicle motion using Model Predictive Control (MPC); 3) a reconfigurable control allocator that redistributes the generalized forces/moments to four wheels with equality constrained optimization.
2014-09-30
Technical Paper
2014-36-0244
Israel João Cancino Junior, Douglas Fazzolari
Abstract Normally the automaker uses a specific Engineering criteria for serviceability with minimum clearance specification. Due to Front Over Hang reduction (Figure 1) regarding to Emerging Markets countries and technology inside in the hood compartment, the H4 bulb serviceability is affected. This paper shows a solution that provides an easy service procedure reducing package and complete sealed connector system for an H4 head lamp bulb. Figure 1 Front over Hang Reduction.
Viewing 121 to 150 of 382