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Viewing 61 to 90 of 33097
2017-03-28
Technical Paper
2017-01-0677
Dongwon Jung, Kosaku Sasaki, Kenji Sugata, Masayoshi Matsuda, Takeshi Yokomori, Norimasa Iida
Abstract Improving the thermal efficiency of spark ignition (SI) engine is strongly required due to its widespread use but considerably less efficiency than that of compression ignition (CI) engine. Although lean SI engine operation can offer substantial improvements of the thermal efficiency relative to that of traditional stoichiometric SI operation, the cycle-to-cycle variations of combustion increases with the level of air dilution, and becomes unacceptable. To improve the stability of lean operation, this study examines the effects of spark discharge pattern and tumble level on cycle-to-cycle variations of combustion at lean limits. The spark discharge pattern was altered by a custom inductive ignition system using ten spark coils and the tumble level was increased by a custom adapter installed in the intake port (tumble adapter).
2017-03-28
Technical Paper
2017-01-0699
Sampad Mukhopadhyay, Sunil Srinivas Badavath, Naeim Henein
Abstract The superior fuel economy of direct injection internal combustion engines (diesel and gasoline) is related to use of a high compression ratio to auto-ignite the fuel and the overall lean combustible mixture. Two of the major problems in diesel engine emissions are the NOx and soot emissions, which are caused by the heterogeneity of the charge and the properties of the diesel fuel. Conventional Direct Injection Spark Ignition Gasoline engines don't have these problems because of the fuel properties particularly its volatility. However, its efficiency and specific power output are limited by the knock, knock produced preignition and the sporadic preignition phenomenon. The Gasoline Direct Injection Compression Ignition (GDICI) engine combines the superior features of the two engines by increasing the compression ratio and use of gasoline as a fuel.
2017-03-28
Technical Paper
2017-01-0720
Omar Ramadan, Luc Menard, David Gardiner, Aaron Wilcox, Gary Webster
Abstract This paper is a continuation of work previously discussed in SAE 2014-01-0179 [1] and SAE 2015-01-0805 [2], which was intended to improve the capability and precision of the Ignition Quality Tester (IQT™) and associated ASTM D6890 [3]/CEN EN 15195 [4]/EI IP 498 [5] Test Methods. The results presented in those two papers indicated how the new generation of IQT™ with the TALM Precision Package upgrade can markedly improve the precision of the ASTM D6890, CEN EN 15195 and EI IP 498 Derived Cetane Number (DCN) test methods. This paper will evaluate the performance of the upgraded instruments over the past 21 months of their participation in ASTM’s National Fuel Exchange Group (NEG) diesel fuel exchange program.
2017-03-28
Technical Paper
2017-01-1616
Scott A. Rush
Abstract Modern automotive manufacturing and after-sale service environments require tailoring of configuration values or “calibrations” within the vehicle’s various electronic control units (ECUs) to that vehicle’s specific option content. Historically, ECU hardware and software limitations have led designers to implement calibratable values using opaque binary blocks tied directly to ECU internal software data structures. Such coupling between calibration data files and ECU software limits traceability and reuse across different software versions and ECU variants. However, more and more automotive ECUs are featuring fast microprocessors, large memories, and preemptive, multi-tasking operating systems that open opportunities to object-oriented approaches. This paper presents the CalDef system for automotive ECU calibration software architecture.
2017-03-28
Technical Paper
2017-01-0003
Tetsuya Tohdo
Abstract We propose a verification method in the field of automotive control systems integrating the concepts of Formal Methods with testing, aiming at efficient and reliable software development. Although Formal Methods are believed to provide the benefits of their rigorous nature and their inherent capability of automation, only limited cases are known where Formal Methods were applied in system and software development, in practice, due to two major difficulties: appropriate abstraction in modeling and scalability in automated reasoning. Focusing on testing on the other hand, there is the difficulty of selecting reasonable set of tests for given verification objectives. In order to overcome these difficulties, our approach is to present verification criteria for testing to appropriately cover the property with the help of the Formal Method concepts.
2017-03-28
Technical Paper
2017-01-0004
Norbert Wiechowski, Thomas Rambow, Rainer Busch, Alexander Kugler, Norman Hansen, Stefan Kowalewski
Abstract Modern vehicles become increasingly software intensive. Software development therefore is critical to the success of the manufacturer to develop state of the art technology. Standards like ISO 26262 recommend requirement-based verification and test cases that are derived from requirements analysis. Agile development uses continuous integration tests which rely on test automation and evaluation. All these drove the development of a new model-based software verification environment. Various aspects had to be taken into account: the test case specification needs to be easily comprehensible and flexible in order to allow testing of different functional variants. The test environment should support different use cases like open-loop or closed-loop testing and has to provide corresponding evaluation methods for continuously changing as well as for discrete signals.
2017-03-28
Technical Paper
2017-01-0005
Yun Liu, Sung-Kwon Hong, Tony Ge
Abstract Powertrain drivability evaluation and calibration is an important part of vehicle development to enhance the customer experience. This step mainly takes place on vehicle testing very late in the product development cycle, and is associated with a considerable amount of prototype, test facility, human resource and time cost. Design change options at this stage are also very limited. To reduce the development cost, a model based computer aided engineering (CAE) method is introduced and combined with hardware-in-the-loop (HIL) simulation technology. The HIL simulation method offers a possibility for drivability prediction and development in early phase of product cycle. This article describes the drivability HIL simulation process under development in Ford. The process consists of real time capable multi-domain CAE model integration, powertrain control module (PCM) and HIL simulator interface development and drivability HIL simulation.
2017-03-28
Technical Paper
2017-01-0006
Harald Bucher, Clemens Reichmann, Juergen Becker
Abstract The increasing complexity of electric/electronic architectures (EEA) in the automotive domain raised the necessity of model-based development processes for the design of such heterogeneous systems, which combine different engineering principles with different viewpoints. High-level simulation is a great means to evaluate the EEA in the concept phase of the design, since it reduces costly real-world experiments. However, model-based EEA design and analysis as well as its simulation are often separate processes in the development lifecycle. In this paper, we present a novel approach that extends state-of-the-art model-based systems engineering principles of EEA by a behavior specification reusing library components. The specification is seamlessly integrated in the development process of a single source EEA model. Therewith, the starting point is the abstract logical function architecture of the EEA.
2017-03-28
Technical Paper
2017-01-0007
Jose-Guillermo Saavedra, Asaad Makki, Raciel Cruz
Abstract The advancement in connectivity technology is driving a shift in business models in almost every field. Automakers need to adapt to a new business model in which the platform (automobile) and the mobility solutions (Devices and Services) are enabled by a strong dynamic connectivity. To succeed in this business model, it is imperative to deliver an unparalleled customer experience. Traditional customer experiences focused only in the platform (automobile) are no longer sufficient to address the mobility needs. The development of in-vehicle features should consider both the platform and the connectivity in a single development scope. This paradigm shift sets new challenges for the in-vehicle features designers. Designers have to speak not only the language of the experience but rather a language to address different levels of abstractions to ensure effective communication with all stakeholders and developers including those outside the organization.
2017-03-28
Technical Paper
2017-01-0012
Zia Hossain, Shengling Deng, Jim Sellers, Gary Loechelt, Mo Grimaldi, Irene Wan, Emily Linehan, Alexander Young, Ali Salih
Abstract To meet the increasing demand for lower RDS(ON) MOSFETs in medium voltage automotive applications, the shielded gate trench MOSFET architecture is becoming increasingly popular in recent years for its ability to achieve both lower RDS(ON) and faster switching speed. The lower specific drain-to-source resistance (RDS(ON).Area) translates into smaller chip size and consequently cheaper die cost for the end customers. Furthermore, shielded gate trench architecture offers smaller gate-to-drain capacitance by utilizing the shielding effect from the shield-poly, leading to lower G-D charge (QGD), faster switching speed, and increased dv/dt immunity. A comprehensive portfolio of medium voltage shielded gate power MOSFET products in several voltage classes (40V, 60V, 80V, and 100V) in automotive and industrial markets is presented in this paper.
2017-03-28
Technical Paper
2017-01-0013
Gaurav Gupta, Ujjwal Modi
Abstract Flickering problems in automotive vehicles have been observed from long time. After assessing numerous vehicles it was observed that whenever the hazard lights in a vehicle are activated, it leads to flickering problems in lights/small electrical components. This paper is to provide the solution for flickering snags in electrical components in a vehicle. The lights that are analyzed to be flickering/wavering are generally small loads such as LEDs in the bus roof area, small parking lamps, LEDs used in instrument clusters, cabin lamps, etc. The flickering in lights can turn out to be very unappealing at certain times. This absurd behavior can lead to extreme discomfort to the passengers and can also be a source of major distraction to the driver. This study presents the design & development for a vehicle platform & implementation that assesses the problem. Because of abrupt behavior of flasher circuits, voltage surges are observed, leading to flickering problems.
2017-03-28
Technical Paper
2017-01-0018
Jeong Chan Kim, Kai Richter, Myung Hyun Koo, Matthias Hagner, Chung Hi Lee
Abstract Along with the efforts to cope with the increase of functions which require higher communication bandwidth in vehicle networks using CAN-FD and vehicle Ethernet protocols, we have to deal with the problems of both the increased busload and more stringent response time requirement issues based on the current CAN systems. The widely used CAN busload limit guideline in the early design stage of vehicle network development is primarily intended for further frame extensions. However, when we cannot avoid exceeding the current busload design limit, we need to analyze in more detail the maximum frame response times and message delays, and we need good estimation and measurement techniques. There exist two methods for estimating the response time at the design phase, a mathematical worst-case analysis that provides upper bounds, and a probability based distributed response time simulation.
2017-03-28
Technical Paper
2017-01-0021
Takashi Yasuda, Hideki Goto, Hiroki Keino, Kaoru Yoshida, Hiroyuki Mori, Miyuki Mizoguchi
Abstract In recent years, the demand for high-speed/high-bandwidth communication for in-vehicle networks has been increasing. This is because the usage of high-resolution screens and high-performance rear seat entertainment (RSE) systems is expanding. Additionally, it is also due to the higher number of advanced driver assistance systems (ADAS) and the future introduction of autonomous driving systems. High-volume data such as high definition sensor images or obstacle information is necessary to realize these systems. Consequently, automotive Ethernet, which meets the requirements for high-speed/high-bandwidth communication, is attracting a lot of attention. The application of automotive Ethernet to in-vehicle networks requires that technology developments satisfy EMC performance requirements. In-vehicle EMC requirements consist of two parts: emission and immunity. The emission requirement is to restrict the electromagnetic noise emitted from vehicle.
2017-03-28
Journal Article
2017-01-0578
Pinaki Pal, Daniel Probst, Yuanjiang Pei, Yu Zhang, Michael Traver, David Cleary, Sibendu Som
Abstract Fuels in the gasoline auto-ignition range (Research Octane Number (RON) > 60) have been demonstrated to be effective alternatives to diesel fuel in compression ignition engines. Such fuels allow more time for mixing with oxygen before combustion starts, owing to longer ignition delay. Moreover, by controlling fuel injection timing, it can be ensured that the in-cylinder mixture is “premixed enough” before combustion occurs to prevent soot formation while remaining “sufficiently inhomogeneous” in order to avoid excessive heat release rates. Gasoline compression ignition (GCI) has the potential to offer diesel-like efficiency at a lower cost and can be achieved with fuels such as low-octane straight run gasoline which require significantly less processing in the refinery compared to today’s fuels.
2017-03-28
Journal Article
2017-01-0581
Stephen C. Burke, Matthew Ratcliff, Robert McCormick, Robert Rhoads, Bret Windom
Abstract In some studies, a relationship has been observed between increasing ethanol content in gasoline and increased particulate matter (PM) emissions from vehicles equipped with spark ignition engines. The fundamental cause of the PM increase seen for moderate ethanol concentrations is not well understood. Ethanol features a greater heat of vaporization (HOV) than gasoline and also influences vaporization by altering the liquid and vapor composition throughout the distillation process. A droplet vaporization model was developed to explore ethanol’s effect on the evaporation of aromatic compounds known to be PM precursors. The evolving droplet composition is modeled as a distillation process, with non-ideal interactions between oxygenates and hydrocarbons accounted for using UNIFAC group contribution theory. Predicted composition and distillation curves were validated by experiments.
2017-03-28
Technical Paper
2017-01-1137
Xiaofeng Yin, Han Lu, Xiaohua Wu, Yongtong Zhang, Wei Luo
Abstract For the vehicle equipped with stepped automatic transmission (SAT) that has a fixed number of gears, gearshift schedule is crucial to improve the comprehensive performance that takes into account power performance, fuel economy, and driver’s performance expectation together. To optimize and individualize the gearshift schedule, an optimization method and an improved performance evaluation approach for multi-performance gearshift schedule were proposed, which are effective in terms of reflecting the driver's expectation on different performance. However, the proposed optimization method does not consider the influence of the road slope on the comprehensive performance. As the road slope changes the load of vehicle that is different from the load when a vehicle runs on a level road, the optimized gearshift schedule without considering road slope is obviously not the optimal solution for a vehicle equipped with SAT when it runs on ramp.
2017-03-28
Journal Article
2017-01-0533
Paul Dekraker, Mark Stuhldreher, Youngki Kim
Abstract The U.S. Environmental Protection Agency’s (EPA’s) Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) tool was created to estimate greenhouse gas (GHG) emissions from light-duty vehicles. ALPHA is a physics-based, forward-looking, full vehicle computer simulation capable of analyzing various vehicle types with different powertrain technologies, showing realistic vehicle behavior, and auditing of all energy flows in the model. In preparation for the midterm evaluation (MTE) of the 2017-2025 light-duty GHG emissions rule, ALPHA has been refined and revalidated using newly acquired data from model year 2013-2016 engines and vehicles. The robustness of EPA’s vehicle and engine testing for the MTE coupled with further validation of the ALPHA model has highlighted some areas where additional data can be used to add fidelity to the engine model within ALPHA.
2017-03-28
Technical Paper
2017-01-1663
Alan Druschitz, Christopher Williams, Erin Connelly, Bob Wood
Abstract Binder jetting of sand molds and cores for metal casting provides a scalable and efficient means of producing metal components with complex geometric features made possible only by Additive Manufacturing. Topology optimization software that can mathematically determine the optimum placement of material for a given set of design requirements has been available for quite some time. However, the optimized designs are often not manufacturable using standard metal casting processes due to undercuts, backdraft and other issues. With the advent of binder-based 3D printing technology, sand molds and cores can be produced to make these optimized designs as metal castings.
2017-03-28
Technical Paper
2017-01-1671
Johannes Bach, Marc Holzäpfel, Stefan Otten, Eric Sax
Abstract Enhanced technological capabilities render the application of various, increasingly complex, functional concepts for automated driving possible. In the process, the significance of automotive software for a satisfactory driving experience is growing. To benefit from these new opportunities, thorough assessment in early development stages is highly important. It enables manufacturers to focus resources on the most promising concepts. For early assessment, a common approach is to set up vehicles with additional prototyping hardware and perform real world testing. While this approach is essential to assess the look-and-feel of newly developed concepts, its drawbacks are reduced reproducibility and high expenses to achieve a sufficient and balanced sample. To overcome these drawbacks, new flexible, realistic and preferably automated virtual test methods to complement real world verification and validation are especially required during early development phases.
2017-03-28
Technical Paper
2017-01-1666
David Weiss, Orlando Rios
Abstract Aluminum alloys containing cerium have excellent castability and retain a substantial fraction of their room temperature strength at temperatures of 200°C and above. High temperature strength is maintained through a thermodynamically trapped, high surface energy intermetallic. Dynamic load partitioning between the aluminum and the intermetallic increases mechanical response. Complex castings have been produced in both permanent mold and sand castings. This versatile alloy system, using an abundant and inexpensive co-product of rare earth mining, is suitable for parts that need to maintain good properties when exposed to temperatures between 200 and 315°C.
2017-03-28
Technical Paper
2017-01-1667
Scott Piper, Mark Steffka, Vipul Patel
Abstract With the increasing content of electronics in automobiles and faster development times, it is essential that electronics hardware design and vehicle electrical architecture is done early and correctly. Today, the first designs are done in the electronic format with circuit and CAD design tools. Once the initial design is completed, several iterations are typically conducted in a “peer review” methodology to incorporate “best practices” before actual hardware is built. Among the many challenges facing electronics design and integration is electromagnetic compatibility (EMC). Success in EMC starts at the design phase with a relevant “lessons learned” data set that encompasses component technology content, schematic and printed circuit board (PCB) layout, and wiring using computer aided engineering (CAE) tools.
2017-03-28
Technical Paper
2017-01-0010
Vinay Vaidya, Ramesh S, Venkatesh Kareti, Smitha K.P., Priti Ranadive
Abstract Currently, Model Based Development (MBD) is the de-facto methodology in automotive industry. This has led to conversions of legacy code to Simulink models. Our previous work was related to implementing the C2M tool to automatically convert legacy code to Simulink models. While the tool has been implemented and deployed on few OEM pilot code-sets there were several improvement areas identified w.r.t. the generated models. One of the improvement areas identified was that the generated model used atomic blocks instead of abstracted blocks available in Simulink. E.g. the generated model used an ADD block and feedback loop to represent an integration operation instead of using an integrator block directly. This reduced the readability of the model even though the functionality was correct. Thus, as a user of the model, an engineer would like to see abstract blocks rather than atomic blocks.
2017-03-28
Technical Paper
2017-01-1676
Hartmut Lackner
Abstract Software systems, and automotive software in particular, are becoming increasingly configurable to fulfill customer needs. New methods such as product line engineering facilitate the development and enhance the efficiency of such systems. In modern, versatile systems, the number of theoretically possible variants easily exceeds the number of actually built products. This produces two challenges for quality assurance and especially testing. First, the costs of conventional test methods increase substantially with every tested variant. And secondly, it is no longer feasible to build every possible variant for the purpose of testing. Hence, efficient criteria for selecting variants for testing are necessary. In this contribution, we propose a new test design method that enables systematic sampling of variants from test cases. We present six optimization criteria to enable control of test effort and test quality by sampling variants with different characteristics.
2017-03-28
Technical Paper
2017-01-0234
Assam Alzookery
In today’s era, real time data tagging is significant for research and development of new automotive technology. The ability to tag and classify data increases operational efficiency in terms of improvements of algorithms and enhancements of sensors used in current and future vehicle technology. Real Time Data Tagging Software (RT-DTS) application was developed to use in conjunction with the data acquisition system. In addition, this application will help the user to tag quickly and efficiently, identify data that are unique and significant enough to undergo extensive analyses to further enhance and improve algorithms and features that correlates to increased safety, which is the paramount goal across the automotive industry. The application currently runs in iOS and can be installed on Apple devices.
2017-03-28
Technical Paper
2017-01-0960
Pankaj Kumar, Imad Makki
Traditionally, a three-way catalyst (TWC) is controlled to a set heated exhaust gas oxygen (HEGO) sensor voltage (typically placed after the monitored catalyst) that corresponds to optimal catalyst efficiency. This limits the control action, as we rely on emissions breakthrough at the HEGO sensor to infer the state of catalyst. In order to robustly meet the super ultra-low emission regulations, a more precise TWC control around the oxidation level of catalyst is desirable. In this work, we developed a comprehensive set of models to predict the oxygen storage capacity using measured in-vehicle signals only. This is accomplished by developing three models; the first model is a linear in parameter regression model to predict the feed gas emissions from measured signals like engine speed and air-to-fuel ratio (A/F). The second model is a low-dimensional physics based model of the three-way catalyst to predict the exhaust emissions and oxidation state of the catalyst.
2017-03-28
Technical Paper
2017-01-1023
Yaqun Jiang, C. Hsieh, Georg Festag, Masood Ahmed, William Jiang
Large axial displacement at the edge of a flywheel caused a clutch fail to disengage in high-speed rotation. To find out the root cause and solve the problem, a numerical procedure is proposed to investigate the vibration source and to understand dynamic behavior of the crank-train system. A simulation of the whole engine system including block, crankshaft, piston and connecting rod was performed with AVL/Excite. The baseline model was correlated with measurement. A comprehensive study was conducted for a set of flywheel and crankshaft models with different materials and unbalance masses. The contribution to flywheel wobbling of each vibration order was carefully investigated, and an optimal design was presented.
2017-03-28
Technical Paper
2017-01-0669
Matthieu LEGUILLE, Frederic Ravet, Jerome Le Moine, Eric Pomraning, Keith Richards, P. K. Senecal
Abstract The current trend of downsizing used in gasoline engines, while reducing fuel consumption and CO2 emissions, imposes severe thermal loads inside the combustion chamber. These critical thermodynamic conditions lead to the possible auto-ignition (AI) of fresh gases hot-spots around Top-Dead-Center (TDC). At this very moment where the surface to volume ratio is high, wall heat transfer influences the temperature field inside the combustion chamber. The use of a realistic wall temperature distribution becomes important in the case of a downsized engine where fresh gases hot spots found near high temperature walls can initiate auto-ignition. This paper presents a comprehensive numerical methodology for an accurately prediction of thermodynamic conditions inside the combustion chamber based on Conjugate Heat Transfer (CHT).
2017-03-28
Technical Paper
2017-01-0971
Uladzimir Budziankou, Thomas Lauer, Xuehai Yu, Brian M Schmidt, Nam Cho
Experimental studies have shown that knitted wiremesh mixers reduce the formation of solid deposits and improve ammonia homogenization in automotive SCR systems. However, their implementation in CFD models remains a major challenge due to the complex WM geometry. It was the aim of the current study to investigate droplet WM interaction. Essential processes, such as secondary droplet generation, wall film formation, and heat exchange, were analyzed in detail and a numerical model was set up. A box with heat resisting glass was used to study urea-water solution spray impingement on a WM under a wide range of operating conditions. High speed videography was used to identify the impingement regimes. Infrared thermography was applied to investigate WM cooling. In order to determine the impact of the WM on the spray characteristics, the droplet spectrum was measured both upstream and downstream of the WM using the laser diffraction method.
2017-03-28
Technical Paper
2017-01-0968
Anand Srinivasan, Saurabh Joshi, Yadan Tang, Di Wang, Neal Currier, Aleksey Yezerets
Abstract Commercial Cu-Zeolite SCR catalyst can store and subsequently release significant amount of H2O. The process is accompanied by large heat effects. It is critical to model this phenomenon to design aftertreatment systems and to provide robust tuning strategies to meet cold start emissions and low temperature operation. The complex reaction mechanism of water adsorption and desorption over a Cu-exchanged SAPO-34 catalyst at low temperature was studied through steady state and transient experiments. Steady state isotherms were generated using a gravimetric method and then utilized to predict water storage interactions with respect to feed concentration and catalyst temperature. Transient temperature programmed desorption (TPD) experiments provided the kinetic information required to develop a global kinetic model from the experimental data. The model captures fundamental characteristics of water adsorption and desorption accompanied by the heat effects.
2017-03-28
Technical Paper
2017-01-0961
Ray Host, Paul Ranspach, Bruce Anderson, Michael Collareno, George Tapos, Cornelius Henderson
Abstract In recent years, the EPA has implemented a requirement for monitoring the air fuel ratio balance in multi-cylinder engines such that those imbalances may not be so great as to cause the tailpipe emissions level to exceed 1.5 times the nominal emissions standard. Such imbalances may be the result of production fuel injector variation, contamination, leaks, or other malfunctions which cause the air or fuel rate to vary across the cylinders controlled by a single oxygen sensor. For many diagnostic systems that rely on the signal from the oxygen sensor, to achieve compliance to the new diagnostic standard, the sensor must see the signal from each cylinder equally. The aftertreatment system must also be robust to individual cylinder air fuel ratio variation. This paper introduces the concept of catalyst zone flow, a condition in which different cylinders of a multi-cylinder engine use different portions of the catalyst brick.
Viewing 61 to 90 of 33097