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Viewing 181 to 210 of 1655
2014-10-13
Technical Paper
2014-01-2796
Heju Zhu, Wanying Li, Hanguo Tao, Jun Li, Xiuhua Sui
Abstract In order to study and evaluate the effect of sulfated ash in different diesel engine lubricants on the performance and durability of diesel particulate filter (DPF), the two engine oils of API CI-4 and CJ-4 with different sulfated ash levels are used respectively in the durability tests of two DPF systems. Moreover, the pressure drop, ash loading and filtration efficiency of the two DPFs, deposits in the inlets and outlets of the DPFs, intake flow rate and fuel consumption rates of engine are measured and compared. The test results show that: Compared to the API CI-4 which has more ash in the formulation than the API CJ-4, the API CJ-4 shows a markedly excellent performance on the lower ash loading and longer service interval and life for DPF, as well as lower fuel consumption rate for the diesel engine with DPF.
2014-09-30
Technical Paper
2014-36-0279
Alvaro C. Michelotti, André L. Paza, Cristiano Foppa, Tiago A. Martins
Abstract Reliability growth method is as a supporting tool for the production readiness plan of a new product line, in order to have an estimated probability of field failures during normal production. This is accomplished in the case study presented herein using prototypes test bench data. Evaluation is carried to verify its adequacy to support new product launch. Additionally, continuous improvement and evaluation of design change impact on product performance is another potential application of the method. In the case study a reliability growth planning and assessment is conducted prior to a new alternator pulley product line launch to confirm initial durability targets of the product could be achieved during transition from R&D validated prototype to the mass production items of the new product line. It includes efforts from Product Engineering during development stages until Start Of Production (SOP).
2014-09-30
Technical Paper
2014-36-0219
Marcos Colombini, Teo Rocha
Abstract Product Design is a process of creating new product by an organization or business entity for its customer. Being part of a stage in a product life cycle, it is very important that the highest level of effort is being put in the stage. The Design for Six Sigma (DFSS) methodology consists of a collection of tools, needs-gathering, engineering, statistical methods, and best practices that find use in product development. DFSS has the objective of determining the needs of customers and the business, and driving those needs into the product solution so created. In this paper the DFSS methodology is employed to develop the optimal solution to enhance sound transmission loss in a vehicle front of dash pass-through. An integrated approach using acoustic holography and beamforming Noise Source Identification (NSI) techniques is presented as a manner to improve sound insulation during vehicle development.
2014-09-30
Technical Paper
2014-36-0174
Ygor Henrique de Almeida, Roberto Rossy Chaves, Fabrício Cardinali Rezende, Tiago Augusto Carneiro Calijorne, Juan Carlos Horta Gutiérrez
Abstract Currently the durability test of FIAT vehicles powertrain suspension system is performed in pattern roads that reproduces conditions which the vehicle is submitted by costumer during product life cycle. The test done in these roads is time consuming and expensive. Experimental Engineers, for quite some time, have endeavored in doing automotive components fatigue tests in the lab. These environments provide more controlled test conditions and enable a less time consuming test. This work analyzes, over one of the three powertrain system attachment points of a passenger vehicle, differences that are found between a test performed in pattern roads and a test performed in a 6DOF road simulator. As conclusion, presents alternatives to perform the test of these components in lab using a 6DOF road simulator.
2014-09-30
Technical Paper
2014-36-0142
Luis Alberto Pargas Carmona
Abstract A vehicle is a product that encloses high levels of complexity. Assessing its quality requires taking into account several variables simultaneously. Usually, this kind of analysis is made over one variable at a time, ignoring the multidimensional nature of the quality. This is even more critical when two or more vehicles are included in the analysis (e.g. for benchmarking purposes), or when the aim of the analysis is to evaluate the performance of more than one variable over time. This study presents an overview of the biplot, which is a low-dimensional representation of observations and variables, and the possibility to use it in monitoring multiple quality variables.
2014-09-30
Technical Paper
2014-36-0103
Demerson Alves de Campos
Abstract Over recent years, demands for fuel-efficient vehicles have increased with the rise of the fuel price and public concerns on environment. Recently, application of lightweight materials is increasing in the automobile industry in order to improve mass reduction and consequently fuel efficiency. On this particular study, with a goal of developing a Lightweight Fixed Steering Column, it was identified an opportunity to replace fixed steering column metallic upper and lower brackets by polymeric material. In order to fulfill NVH, Crash, Durability and Performance requirements, a DFSS methodology has been applied. As a result, It was achieved ∼51% of mass reduction, ∼10% of performance improvement with ∼14% of cost increase.
2014-09-30
Technical Paper
2014-36-0405
Matheus Ferreira, Adalto Silva, Mário Praça, Sandra Costa
Abstract Lead free bronze substrate associated with a lead free electroplated coating has been the standard bearing material technology for medium size Diesel engines. However the increasing engine demands are driving this technology to the limit. With the increase of Peak Cylinder Pressure (PCP) to improve power density and reduce CO2 emissions, the bearings are subjected to higher loads which usually reduce their durability. The new operating conditions are more prone to wear and eventually scuffing occurrences. Therefore materials with higher scuffing and wear resistance without a significant cost increase are demanded. To meet the requirements of highly loaded Medium Duty Diesel (MDD) applications, a lead free material based on a high resistant bronze substrate associated with a polymeric coating was developed. The polymer is sprayed onto the substrate and cured on a high temperature to provide performance improvement and adequate thickness control.
2014-09-30
Technical Paper
2014-36-0304
Leonardo Navarenho de Souza Fino, Rafael Navarenho de Souza
Abstract The reliability of the microelectronic devices and circuits is a major factor that determines both their manufacturability and application lifetime. One of the most pervasive problems on the integrated circuit (IC) industry is the electrostatic discharging (ESD) failure. ESD damage has become more prevalent in newer technologies due to the higher susceptibility of smaller circuit components. In addition, the changes on the IC technology have also changed the ESD protection techniques, requiring a continuous improvements and studies. ESD causes about 40 % of IC failures and represents, annually, a loss of billions of dollars due to repair, rework, shipping, labor and overhead costs associated with the damage, which highlights the importance of fundamental understanding of ESD aspects and design of efficient ESD protection.
2014-09-30
Technical Paper
2014-01-2430
Rajendra Vivekananda Hosamath, Muralidhar Nagarkatte
Abstract All top ranking automobile companies in the world believe in single word “Quality” and maintaining quality standards is a philosophy, a belief in which we live, a task which cannot be put aside for another day. To achieve the world class quality standards Divgi-Warner meticulously follows a highly effective tool known as Quality System Basics (QSB).QSB helps Divgi-Warner to preserve integrity of commitment to achieve manufacturing excellence. This case study covers the Quality System Basics implementation experience of Divgi-Warner Pvt. Ltd. (DWPL) India, a BorgWarner's plants located at Pune and Sirsi in India.
2014-09-30
Technical Paper
2014-01-2297
Mehmet Bakir, Murat Siktas, Serter Atamer
Abstract In today's world, there are a prominent number of weight and cost reduction projects within the vehicle engineering development activities. Regarding this phenomenon, a complete optimization study is applied to a leaf spring assembly, which has 4 leaves and which is used in heavy duty trucks, by reducing the number of leaves down to 3 together with weight and cost reductions. At the first step of the project, the stiffness of the leaf spring is calculated with in-house software based on mathematical calculations using the thickness profile of the leaves. Then the results of these calculations are compared with non-linear elastic leaf spring calculations which are conducted with FEA. This elastic leaf spring finite element model is transferred into Multi-Body-Simulation (MBS) model in order to determine the forces acting on the leaf spring.
2014-09-30
Journal Article
2014-01-2307
Zhigang Wei, Limin Luo, Shengbin Lin
This paper reviews the correlation concepts and tools available, with the emphasis on their historical origins, mathematical properties and applications. Two of the most commonly used statistical correlation indicators, i.e., modal assurance criterion (MAC) for structural deformation pattern identification/correlation and the coefficient of determination (R2) for data correlation are investigated. The mathematical structure of R2 is critically examined, and the physical meanings and their implications are discussed. Based on the insights gained from these analyses, a data scatter measure and a dependency measure are proposed. The applications of the measures for both linear and nonlinear data are also discussed. Finally, several worked examples in vehicle dynamics analysis and statistical data analyses are provided to demonstrate the effectiveness of these concepts.
2014-09-30
Technical Paper
2014-01-2306
Mathialagan Balaji, Hemant Bhatkar, Jeya Kumar Ranjith Kumar, Ananthan Anbazhagan, Pramod Palkar
Abstract Rear axles are subjected to bending and torsion loads out of which Bending loads are predominant. In case of Off road vehicles Bi Axial- combination of Bending and torsion loads were predominant, because of axle construction and vehicle usage pattern. Defined test procedures are available for bending durability and torsional durability evaluation of axles. In this experiment, new test methodology was developed for Bi Axial durability evaluation of Off road vehicle rear axle with single servo hydraulic linear actuator. For creating Bi Axial load condition, we may need multiple actuators and complicated fixtures. Axle wheel end is constrained at an angle with suitable fixtures for creating the bending and torsional forces together in the axle. Servo hydraulic linear actuator with suitable loading arm is used for applying the test torque in the axle input flange.
2014-09-30
Technical Paper
2014-01-2312
Venkatesan Chokkalingam, Mohan Rao
Abstract The durability of the components in a vehicle plays one of the major roles in its life cycle cost. The powertrain mount is one such component since its rubber characteristics have significant impact on the vehicle's NVH and fatigue life. This paper presents the enhanced durability benefits obtained by changing the polymer composition, manufacturing methods and design optimization of a powertrain mount for an off-road commercial vehicle. The methodology involved characterization[2] of the existing mount, arriving a new compound formulation, making of prototypes, experimental validation for durability[3] and repeatability in the laboratory combined with rigorous on field vehicle trials. NVH measurements were also carried out on the improved mounts. The above exhaustive exercise resulted in the development of a comprehensively far better mount than an existing mount with improved durability without compromise on NVH properties.
2014-09-30
Journal Article
2014-01-2308
Zhigang Wei, Shengbin Lin, Limin Luo, Litang Gao
Road vibrations cause fatigue failures in vehicle components and systems. Therefore, reliable and accurate damage and life assessment is crucial to the durability and reliability performances of vehicles, especially at early design stages. However, durability and reliability assessment is difficult not only because of the unknown underlying damage mechanisms, such as crack initiation and crack growth, but also due to the large uncertainties introduced by many factors during operation. How to effectively and accurately assess the damage status and quantitatively measure the uncertainties in a damage evolution process is an important but still unsolved task in engineering probabilistic analysis. In this paper, a new procedure is developed to assess the durability and reliability performance, and characterize the uncertainties of damage evolution of components under constant amplitude loadings.
2014-09-30
Journal Article
2014-01-2347
Britney J. McCoy, Arman Tanman
Abstract In-use testing of diesel emission control technologies is an integral component of EPA's verification program. Device manufacturers are required to complete in-use testing once 500 units have been sold. Additionally, EPA conducts test programs on randomly selected retrofit devices from installations completed with grants by the National Clean Diesel Campaign. In this test program, EPA identified and recovered a variety of retrofit devices, including diesel particulate filters (DPFs) and diesel oxidation catalysts (DOCs), installed on heavy-duty diesel vehicles (on-highway and nonroad). All of the devices were tested at Southwest Research Institute in San Antonio, Texas. This study's goal was to evaluate the durability, defined here as emissions performance as a function of time, of retrofit technologies aged in real-world applications.
2014-09-28
Technical Paper
2014-01-2520
Qiang Wang, Gang Qi, Guangrong Zhang, Xinyu Pu
Abstract A brake durability experimental method is proposed to simulate a brake durability vehicle road test. Brake judder and noise often occur in brake durability road testing. Brake judder is difficult to address because of its many potential causes, such as assembly run out, component stiffness, lining characteristics, thermal coning/hot spot/thermal instability and corrosion. There are currently several test procedures to predict brake thermal roughness and pad cleaning corrosion performance for preventing brake judder. Brake durability vehicle road testing is performed to check brake NVH and wear; examples include the Mojacar test in Spain and the Huangshan test in China. Brake energy intensity and road vibration are the significant factors that cause brake rotor thickness variation, which generates brake judder in public road testing.
2014-09-16
Technical Paper
2014-01-2208
Michael Baldwin
Abstract This paper will illustrate how the increasing electrical power demands of military and aerospace applications can continue to successfully be met by high performance electromechanical relays. To meet these higher demands engineering compatibility must be properly understood between the intended application demands and relay switching performance parameters. With high performance electromechanical relays continuing to play a critical part in military and aerospace applications it is more important than ever that engineers capture all of the electrical power switching requirements. A critical area within powering military and aerospace systems is relay life when capacitive load switching. Capacitive loads generate high current levels that are transient in duration and often adversely affect the relay lifespan at the component level and the military or aerospace application reliability at the systems level.
2014-09-16
Technical Paper
2014-01-2160
Wei Wu, Yeong-Ren Lin, Louis Chow
Abstract In this paper, we address the thermal management issues which limit the lifespan, specific power and overall efficiency of an air-cooled rotary Wankel engine used in Unmanned Air Vehicles (UAVs). Our goal is to eliminate the hot spots and reduce the temperature gradients in the engine housing and side plates by aggressive heat spreading using heat pipes. We demonstrate by simulation that, for a specific power requirement, with heat spreading and more effective heat dissipation, thermal stress and distortion can be significantly reduced, even with air cooling. The maximum temperature drop was substantial, from 231°C to 129°C. The temperature difference (measure of temperature uniformity) decreased by 8.8 times (from 159°C to 18°C) for a typical UAV engine. Our heat spreaders would not change the frontal area of the engine and should have a negligible impact on the installed weight of the propulsion assembly.
2014-09-16
Technical Paper
2014-01-2262
Rostislav Sirotkin, Galina Susova, Gennadii Shcherbakov
Abstract Within the Russian aviation industry the necessary level of reliability risks related to the failures of aircraft mechanical parts and systems vital to the safety of flight is assured via the system of activities aimed at influencing the parameters of critical parts (CP). The goal of the system is to provide a relationship between activities aimed at prevention of dangerous failures at all phases of airplane life cycle. The system operation is regulated by the normative documents and by controlling their observance. Normative documents containing requirements and recommendations were developed about 15 years ago based on the industry experience and traditions and taking into account the requirements of AS9100 series of international standards [2] wherever possible. The documents were developed taking into account typical safety management errors outlined in [1].
2014-09-16
Journal Article
2014-01-2128
Ephraim Suhir, Alain Bensoussan
Abstract The attributes of and challenges in the recently suggested probabilistic design for reliability (PDfR) concept, and the role of its major constituents - failure oriented accelerated testing (FOAT) and physically meaningful predictive modeling (PM) - are addressed, advanced and discussed. The emphasis is on the application of the powerful and flexible Boltzmann-Arrhenius-Zhurkov (BAZ) model, and particularly on its multi-parametric aspect. The model can be effectively used to analyze and design optoelectronic (OE) devices and systems with the predicted, quantified, assured, and, if appropriate and cost-effective, even maintained probability of failure in the field. The numerical example is carried out for an OE system subjected to the combined action of the ionizing radiation and elevated voltage as the major stimuli (stressors). The measured leakage current is used as a suitable characteristic of the degree of degradation.
2014-09-16
Journal Article
2014-01-2144
Marco Amrhein, Jason Wells, Eric Walters, Seana McNeal, Brett Jordan, Peter Lamm
Abstract Transient operating conditions in electrical systems not only have significant impact on the operating behavior of individual components but indirectly affect system and component reliability and life. Specifically, transient loads can cause additional loss in the electrical conduction path consisting of windings, power electronic devices, distribution wires, etc., particularly when loads introduce high peak vs. average power ratios. The additional loss increases the operating temperatures and thermal cycling in the components, which is known to reduce their life and reliability. Further, mechanical stress caused by dynamic loading, which includes load torque cycling and high peak torque loading, increases material fatigue and thus reduces expected service life, particularly on rotating components (shaft, bearings).
2014-09-16
Journal Article
2014-01-2110
David Gras, Christophe Pautrel, Amir Fanaei, Gregory Thepaut, Maxime Chabert, Fabien Laplace, Gonzalo Picun
Abstract In this paper we present a set of integrated circuits specifically designed for high temperature power applications such as isolated power transistor drivers and high efficiency power supplies. The XTR26010 is the key circuit for the isolated power gate drive application. The XTR26010 circuit has been designed with a high focus in offering a robust, reliable and efficient solution for driving a large variety of high-temperature, high-voltage, and high-efficiency power transistors (SiC, GaN, Si) existing in the market. The XTR40010 is used for isolated data communication between a microcontroller or a PWM controller and the power driver (XTR26010). The isolated power transistor driver features a dual turn-on channel, a turn-off channel and a Miller Clamp channel with more than 3A peak current drive strength for each channel. The dV/dt immunity between XTR26010 and XTR40010 exceeds 50kV/μs.
2014-09-16
Technical Paper
2014-01-2197
Didier Regis, Julie Berthon, Marc Gatti
Abstract For more than 40 years, Gordon Moore's experimental law has been predicting the evolution of the number of transistors in integrated circuits, thereby guiding electronics developments. Until last years, this evolution did not have any measurable impact on components' quality; but the trend is beginning to reverse. This paper is addressing the impact of scaling on the reliability of integrated circuits. It is analyzing - from both qualitative and quantitative point of view - the behavior of Deep Sub-Micron technologies in terms of robustness and reliability. It is particularly focusing on three basics of safety analyses for aeronautical systems: failure rates, lifetimes and atmospheric radiations' susceptibility.
2014-05-07
Technical Paper
2014-36-0038
Fabio Augusto Schuh, Leandro Luís Corso, Leonardo Hoss
Abstract Applying knowledge available at technical literature for cycle counting, damage caused by each load cycle through S-N curve, and fatigue damage accumulation by Palmgren-Miner rule, durability prediction is performed for a leafspring of a commercial vehicle with 6×4 suspension system. Max principal tension is measured by means of strain gages in the most representative points for fatigue life of the leafspring, determined with FEA, while vehicle runs over off-road track in a proving ground. Load and tension are also measured in a laboratory bench test for this component. Correlation between off-road track and bench test is then performed. Finally, representative samples of the component are tested with dynamic loading until fatigue fracture in bench test, and using data from these tests, statistical analysis is performed with application of Weibull distribution, allowing life prediction in statistical terms.
2014-04-01
Technical Paper
2014-01-0070
Ralph S. Shoberg, Jeff Drumheller
Abstract Reliable wheel attachment must start with proper tightening of the lug nuts in order to achieve the clamping force necessary to hold the vehicle's wheels securely for all operating conditions. It is the purpose of this paper to provide a complete overview of the theory and practice of using torque-angle signature analysis methods to examine the installation and audits of wheel lug nuts. An accurate estimate of clamp load can be determined without actually measuring the clamp load. The torque-angle signature analysis, known as “M-Alpha”, performed on tightening and loosening curves provides a powerful tool to understand the integrity of a bolted joint when clamp load data is not available. This analysis technique gives insight into the frictional effects, material properties, and geometric factors that can affect the clamp load attained during the installation process.
2014-04-01
Journal Article
2014-01-0046
Takehito Shiraishi, Yasuo Shimizu
In the automobile industries, weight reduction has been investigated to improve fuel efficiency together with reduction of CO2 emission. In such circumstance, it becomes necessity to make an electric power steering (EPS) more compact and lightweight. In this study, we aimed to have a smaller and lighter EPS gear size by focusing on an impact load caused at steering end. In order to increase the shock absorption energy without increase of stopper bush size, we propose new theory of impact energy absorption by not only spring function but also friction, and a new stopper bush was designed on the basis of the theory. The profile of the new stopper bush is cylinder form with wedge-shaped grooves, and when the new stopper bush is compressed by the end of rack and the gear housing at steering end, it enables to expand the external diameter and produce friction. In this study, we considered the durability in the proposed profile.
2014-04-01
Technical Paper
2014-01-0821
Sunil KV, Sunil Sheepri, Kiran Kandula, Amit Kumar
Abstract The durability evaluation of overhanging components of a vehicle (Ex: horn, radiator) is a challenge to durability engineers as resonance plays an important role in determining their fatigue life. As resonance cannot be avoided always, it is desirable to develop methods to evaluate life of the component in the presence of resonance. Though the existing vibration test standards suggest test profiles to evaluate resonance failures, there are cases in which, these methods do not yield the proving ground results. This may lead to unnecessary overdesign or unrealistic failures. In such cases it is suggested to generate a sweep endurance test procedure customized to the proving ground or actual roads. This paper studies a methodology for generating a sweep endurance test procedure for evaluation of resonating components. Responses like stress and accelerations were measured in test components in proving ground.
2014-04-01
Technical Paper
2014-01-0774
Zhigang Wei, Limin Luo, Shengbin Lin, Dmitri Konson
Abstract A modern definition of quality control and improvement is the reduction of variability in processes and products. The reduced variability can be directly translated into lower costs, better functions and fewer repairs. However, the final quality of processes and products is sometimes derived from other measured variables through some implicit or explicit functional relationships. Sometimes, a tiny uncertainty in a variable can produce a huge uncertainty in a derived quantity. Therefore, the propagation of uncertainty needs to be understood and the individual variables need to be well controlled. More importantly, the critical factors that affect quality the most should be identified and thoroughly investigated. Design of experiments and statistical control plays central roles in finding root cause of failure, reduction of variability and quality improvement.
2014-04-01
Technical Paper
2014-01-0749
Ram Kiran Tholeti, Shyamsundar Kumbhar, Nainish Kumar B, R Govindarajan
Abstract Scooter segment growth is tremendously increasing in India. The increased competition challenges automotive manufacturers to deliver the high quality and high reliable product to the market. Higher reliability involves increased durability testing which involves time and cost. Stress testing a part of durability is initially conducted on prototype vehicles for structural design validation and then later on production units to ensure its structural integrity. The obtained data from the tests can be used for future structural design improvements. Scooters with small tires, suspension limitations transfers more loads to structure, challenges engineers to design robust structure without compromising on weight much. It is necessary to look at Real World Usage Pattern (RWUP) and to create a stress life cycle block for simulation of accelerated testing, thereby optimizing the testing time and the development costs.
2014-04-01
Technical Paper
2014-01-0748
Dong-Hyun Ha, Soon-Cheol Park, Chun-Woo Shin
Abstract Currently, the interest in accelerated reliability testing (ART) of electric vehicles parts has been increasing. In particular, an electric motor and battery are vital components of battery powered electric vehicles. The electric motor has two major roles, to discharge or charge battery when it is driven or braking. For analyzing the exact behavior mechanism of electric motor and predicting lithium-ion battery cell degradation, new accelerated reliability testing technology is required. This paper describes the results of research and development in new approach to reliability testing for electric vehicles. The methodology to measure a precise motor output torque of the rotating rotor using telemetry system was provided. The electric energy quantities as well as the used quantities of the electric power were also analyzed. The results of research and development in new approach to reliability testing for electric vehicles were systematized and reflected in development.
Viewing 181 to 210 of 1655