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Viewing 271 to 300 of 16460
2017-03-28
Technical Paper
2017-01-0620
Chandrakant Parmar, Sethuramalingam Tyagarajan, Sashikant Tiwari, Ravindra Thonge, S Arun Paul
Abstract The engine compartment of passenger car application contains various source which radiates the produced heat and raises the temperature level of the compartment. The rise in compartment temperature increases the body temperature of individual component. The rise in body temperature of critical components can endanger the durability or functionality of the specific component or a system in which it operates. The aim of this paper is to strategize thermal protection of the rear mounted engine and its components of a vehicle having radiator and cooling fan mounted in front. An additional ventilation fan with speed sensor is fitted alongside rear mounted engine and a unique monitoring technique framed in the EMS ECU to protect critical components like HT cables, alternators, ECUs, wiring harness etc. from thermal damage. The EMS continuously monitors the engine speed, vehicle speed and the PWM signal of ventilation fan to ensure the intended operation of the ventilation fan.
2017-03-28
Journal Article
2017-01-0619
Ravi Teja Vedula, Thomas Stuecken, Harold Schock, Cody Squibb, Ken Hardman
Abstract Piston temperature plays a major role in determining details of fuel spray vaporization, fuel film deposition and the resulting combustion in direct-injection engines. Due to different heat transfer properties that occur in optical and all-metal engines, it becomes an inevitable requirement to verify the piston temperatures in both engine configurations before carrying out optical engine studies. A novel Spot Infrared-based Temperature (SIR-T) technique was developed to measure the piston window temperature in an optical engine. Chromium spots of 200 nm thickness were vacuum-arc deposited at different locations on a sapphire window. An infrared (IR) camera was used to record the intensity of radiation emitted by the deposited spots. From a set of calibration experiments, a relation was established between the IR camera measurements of these spots and the surface temperature measured by a thermocouple.
2017-03-28
Technical Paper
2017-01-0631
David C. Ogbuaku, Timothy Potter, James M. Boileau
Abstract The need to increase the fuel-efficiency of modern vehicles while lowering the emission footprint is a continuous driver in automotive design. This has given rise to the use of engines with smaller displacements and higher power outputs. Compared to past engine designs, this combination generates greater amounts of excess heat which must be removed to ensure the durability of the engine. This has resulted in an increase in the number and size of the heat exchangers required to adequately cool the engine. Further, the use of smaller, more aerodynamic front-end designs has reduced the area available in the engine compartment to mount the heat exchangers. This is an issue, since the reduced engine compartment space is increasingly incapable of supporting an enlarged rectangular radiator system.
2017-03-28
Technical Paper
2017-01-0797
Sahil Sane, Tamer Badawy, Naeim Henein
Abstract Cold starting problems of diesel engines are caused mainly by the failure of the auto-ignition process or the subsequent combustion of the rest of the charge. The problems include long cranking periods and combustion instability leading to an increase in fuel consumption in addition to the emission of undesirable unburned hydrocarbons which appear in the exhaust as white smoke. The major cause of these problems is the low temperature and pressure of the charge near the end of the compression stroke and/or the poor ignition quality of the fuel. This paper presents the results of an experimental investigation of cold starting of a high speed diesel engine with ULSD (Ultra Low Sulphur Diesel) and JP8 (Jet Propulsion) fuels at ambient temperature (25°C). A detailed analysis is made of the autoignition and combustion of the two fuels in the first few cycles in the cold start transient.
2017-03-28
Technical Paper
2017-01-0860
PengBo Dong, Jun Yamauchi, Keiya Nishida, Youichi Ogata
Abstract With the aim of improving engine performance, recent trend of fuel injection nozzle design followed by engineers and researchers is focusing on more efficient fuel break up, atomization, and fuel evaporation. Therefore, it is crucial to characterize the effect of nozzle geometric design on fuel internal flow dynamics and the consequent fuel-air mixture properties. In this study, the internal flow and spray characteristics generated by the practical multi-hole (10 holes) nozzles with different nozzle hole length and hole diameter were investigated in conjunction with a series of computational and experimental methods. Specifically, the Computational Fluid Dynamics (CFD) commercial code was used to predict the internal flow variation inside different nozzle configurations, and the high-speed video observation method was applied to visualize the spray evolution processes under non-evaporating conditions.
2017-03-28
Technical Paper
2017-01-1147
Hyunjun Kim, Jingeon Kang, Dongsuk Kum
Abstract Input- and output-split hybrids using a single planetary gear (PG) can provide high fuel economy, but they tend to suffer from low acceleration performance. In order to improve their acceleration performance, speed reduction (multiplication) gears (SRG/SMG) have often been employed in various mass-produced split hybrids. In fact, adding one SRG (SMG) to input- or output-split hybrids can improve not only the acceleration performance, but also the fuel economy. Nevertheless, the full potentials of using SRGs (SMGs) have not yet been thoroughly investigated because the design space of input- and output-split configurations using one SRG (SMG) is huge; 432 configurations can be generated using two PGs where one PG is used as an SRG/SMG. Thus, in order to investigate the impacts of SRG (SMG) within a reasonable time, an efficient analysis procedure is required.
2017-03-28
Technical Paper
2017-01-1140
Yang Xu, Yuji Fujii, Edward Dai, James McCallum, Gregory Pietron, Guang Wu, Hong Jiang
Abstract A transmission system model is developed at various complexities in order to capture the transient behaviors in drivability and fuel economy simulations. A large number of model parameters bring more degree of freedom to correlate with vehicular test data. However, in practice, it requires extensive time and effort to tune the parameters to satisfy the model performance requirements. Among the transmission model, a hydraulic clutch actuator plays a critical role in transient shift simulations. It is particularly difficult to tune the actuator model when it is over-parameterized. Therefore, it is of great importance to develop a hydraulic actuator model that is easy to adjust while retaining sufficient complexity for replicating realistic transient behaviors. This paper describes a systematic approach for reducing the hydraulic actuator model into a piecewise 1st order representation based on piston movement.
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
2017-01-1154
Jimmy Kapadia, Daniel Kok, Mark Jennings, Ming Kuang, Brandon Masterson, Richard Isaacs, Alan Dona, Chuck Wagner, Thomas Gee
Abstract The automotive industry is rapidly expanding its Hybrid, Plug-in Hybrid and Battery Electric Vehicle product offerings in response to meet customer wants and regulatory requirements. One way for electrified vehicles to have an increasing impact on fleet-level CO2 emissions is for their sales volumes to go up. This means that electrified vehicles need to deliver a complete set of vehicle level attributes like performance, Fuel Economy and range that is attractive to a wide customer base at an affordable cost of ownership. As part of “democratizing” the Hybrid and plug-In Hybrid technology, automotive manufacturers aim to deliver these vehicle level attributes with a powertrain architecture at lowest cost and complexity, recognizing that customer wants may vary considerably between different classes of vehicles. For example, a medium duty truck application may have to support good trailer tow whereas a C-sized sedan customer may prefer superior city Fuel Economy.
2017-03-28
Journal Article
2017-01-1184
Kiyoshi Handa, Shigehiro Yamaguchi, Kazuya Minowa, Steven Mathison
Abstract A new hydrogen fueling protocol named MC Formula Moto was developed for fuel cell motorcycles (FCM) with a smaller hydrogen storage capacity than those of light duty FC vehicles (FCV) currently covered in the SAE J2601 standard (over than 2kg storage). Building on the MC Formula based protocol from the 2016 SAE J2601 standard, numerous new techniques were developed and tested to accommodate the smaller storage capacity: an initial pressure estimation using the connection pulse, a fueling time counter which begins the main fueling time prior to the connection pulse, a pressure ramp rate fallback control, and other techniques. The MC Formula Moto fueling protocol has the potential to be implemented at current hydrogen stations intended for fueling of FCVs using protocols such as SAE J2601. This will allow FCMs to use the existing and rapidly growing hydrogen infrastructure, precluding the need for exclusive dispensers or stations.
2017-03-28
Journal Article
2017-01-1183
Kenneth Johnson, Michael J. Veenstra, David Gotthold, Kevin Simmons, Kyle Alvine, Bert Hobein, Daniel Houston, Norman Newhouse, Brian Yeggy, Alex Vaipan, Thomas Steinhausler, Anand Rau
Abstract Fuel cell vehicles are entering the automotive market with significant potential benefits to reduce harmful greenhouse emissions, facilitate energy security, and increase vehicle efficiency while providing customer expected driving range and fill times when compared to conventional vehicles. One of the challenges for successful commercialization of fuel cell vehicles is transitioning the on-board fuel system from liquid gasoline to compressed hydrogen gas. Storing high pressurized hydrogen requires a specialized structural pressure vessel, significantly different in function, size, and construction from a gasoline container. In comparison to a gasoline tank at near ambient pressures, OEMs have aligned to a nominal working pressure of 700 bar for hydrogen tanks in order to achieve the customer expected driving range of 300 miles.
2017-03-28
Journal Article
2017-01-1182
Xin Guo, Xu Peng, Sichuan Xu
Abstract Startup from subzero temperature is one of the major challenges for polymer electrolyte membrane fuel cell (PEMFC) to realize commercialization. Below the freezing point (0°C), water will freeze easily, which blocks the reactant gases into the reaction sites, thus leading to the start failure and material degradation. Therefore, for PEMFC in vehicle application, finding suitable ways to reach successful startup from subfreezing environment is a prerequisite. As it’s difficult and complex for experimental studies to measure the internal quantities, mathematical models are the effective ways to study the detailed transport process and physical phenomenon, which make it possible to achieve detailed prediction of the inner life of the cell. However, review papers only on cold start numerical models are not available. In this study, an extensive review on cold start models is summarized featuring the states and phase changes of water, heat and mass transfer.
2017-03-28
Technical Paper
2017-01-1180
Stefan Brandstätter, Michael Striednig, David Aldrian, Alexander Trattner, Manfred Klell, Tomas Dehne, Christoph Kügele, Michael Paulweber
Abstract The limitation of global warming to less than 2 °C till the end of the century is regarded as the main challenge of our time. In order to meet COP21 objectives, a clear transition from carbon-based energy sources towards renewable and carbon-free energy carriers is mandatory. Polymer electrolyte membrane fuel cells (PEMFC) allow an energy-efficient, resource-efficient and emission-free conversion of regenerative produced hydrogen. For these reasons fuel cell technologies emerge in stationary, mobile and logistic applications with acceptable cruising ranges as well as short refueling times. In order to perform applied research in the area of PEMFC systems, a highly integrated fuel cell analysis infrastructure for systems up to 150 kW electric power was developed and established within a cooperative research project by HyCentA Research GmbH and AVL List GmbH in Graz, Austria. A novel open testing facility with hardware in the loop (HiL) capability is presented.
2017-03-28
Journal Article
2017-01-1179
Tatsuya Arai, Ozaki Takashi, Kazuki Amemiya, Tsuyoshi Takahashi
Abstract Polymer electrolyte membrane fuel cell (PEFC) systems for fuel cell vehicles (FCVs) require both performance and durability. Carbon is the typical support material used for PEFC catalysts. However, hydrogen starvation at the anode causes high electrode potential states (e.g., 1.3 V with respect to the reversible hydrogen electrode) that result in severe carbon support corrosion. Serious damage to the carbon support due to hydrogen starvation can lead to irreversible performance loss in PEFC systems. To avoid such high electrode potentials, FCV PEFC systems often utilize cell voltage monitor systems (CVMs) that are expensive to use and install. Simplifying PEFC systems by removing these CVMs would help reduce costs, which is a vital part of popularizing FCVs. However, one precondition for removing CVMs is the adoption of a durable support material to replace carbon.
2017-03-28
Technical Paper
2017-01-1176
Hafiz S. Khafagy
Abstract Auto stop-start (Engine stop-start, ESS) has become a widely used feature to reduce fuel consumption and CO2 emissions particularly in congested cities. Typically, vehicles equipped with such systems include two DC power sources that are coupled in parallel: a primary and a secondary power source. The primary power source supplies energy to the starter to crank the engine, while the secondary power source supplies energy to the rest of the vehicle electric loads. During an auto-stop event, a controllable switch decouples the two power sources. Moreover, operating current, voltage and the State of Charge (SOC) are monitored to ensure enough energy for the next auto-start event. When any of these operating parameters are below the threshold values, the controllable switch opens to isolate the two batteries and then the engine is automatically started.
2017-03-28
Journal Article
2017-01-1170
Tong Zhang, Chen Wang, Wentai Zhou, Huijun Cheng, Haisheng Yu
Abstract Because a compound power-split transmission is directly connected to the engine, dramatic fluctuations in engine output torque result in strong jerks and torque losses when the hybrid vehicle is in mode transition from electric drive mode to hybrid drive mode. In order to enhance ride comfort and reduce the output torque gap during mode transition process, a brake clutch assisted coordinated control strategy was developed. Firstly, the dynamic plant model of the power-split vehicle including driveline model, engine ripple torque and brake clutch torque was deduced. Secondly, the brake clutch assisted mode transition process was analyzed, and the output torque capability was compared between cases of both brake clutch assisted and unassisted mode transition process. Thirdly, a coordinated control strategy was designed to determine the desired motor torque, brake clutch torque, engine torque, and the moment of fuel injection.
2017-03-28
Journal Article
2017-01-1201
Zhenli Zhang, Zhihong Jin, Perry Wyatt
Abstract Lithium plating is an important failure factor for lithium ion battery with carbon-based anodes and therefore preventing lithium plating has been a critical consideration in designs of lithium ion battery and battery management system. The challenges are: How to determine the charging current limits which may vary with temperature, state of charge, state of health, and battery operations? Where are the optimization rooms in battery design and management system without raising plating risks? Due to the complex nature of lithium plating dynamics it is hard to detect and measure the plating by any of experimental means. In this work we developed an electrochemical model that explicitly includes lithium plating reaction. It enables both determination of plating onset and quantification of plated lithium. We have studied the effects of charging pulses on homogenous plating in order to provide guidance for lithium ion battery design in hybrid applications.
2017-03-28
Journal Article
2017-01-1008
Antti Rostedt, Leonidas D. Ntziachristos, Pauli Simonen, Topi Rönkkö, Zissis C. Samaras, Risto Hillamo, Kauko Janka, Jorma Keskinen
Abstract In this article we present a design of a new miniaturized sensor with the capacity to measure exhaust particle concentrations on board vehicles and engines. The sensor is characterized by ultra-fast response time, high sensitivity, and a wide dynamic range. In addition, the physical dimensions of the sensor enable its placement along the exhaust line. The concentration response and temporal performance of a prototype sensor are discussed and characterized with aerosol laboratory test measurements. The sensor performance was also tested with actual engine exhaust in both chassis and engine dynamometer measurements. These measurements demonstrate that the sensor has the potential to meet and even exceed any requirements around the world in terms of on-board diagnostic (OBD) sensitivity and frequency of monitoring.
2017-03-28
Technical Paper
2017-01-1065
Douglas R. Martin, Benjamin Rocci
Abstract Exhaust temperature models are widely used in the automotive industry to estimate catalyst and exhaust gas temperatures and to protect the catalyst and other vehicle hardware against over-temperature conditions. Modeled exhaust temperatures rely on air, fuel, and spark measurements to make their estimate. Errors in any of these measurements can have a large impact on the accuracy of the model. Furthermore, air-fuel imbalances, air leaks, engine coolant temperature (ECT) or air charge temperature (ACT) inaccuracies, or any unforeseen source of heat entering the exhaust may have a large impact on the accuracy of the modeled estimate. Modern universal exhaust gas oxygen (UEGO) sensors have heaters with controllers to precisely regulate the oxygen sensing element temperature. These controllers are duty cycle based and supply more or less current to the heating element depending on the temperature of the surrounding exhaust gas.
2017-03-28
Technical Paper
2017-01-1068
Jonathan Tigelaar, Krista Jaquet, David Cox, Albert Peter
Turbocharging is significantly changing design and control strategies for Diesel and gasoline engines. This paper will review new advances in the turbocharger speed measurement. Until recently, the highly accurate and fast turbocharger speed data, based on the physical speed sensor signal, has been mainly used to safely decrease conservative safety margins for turbocharger speed and surge limits. In addition to significantly increasing power and low end torque, new generation sensor technology is providing new opportunities to utilize turbocharger speed data.
2017-03-28
Journal Article
2017-01-1094
Yusuke Nakade, Atsushi Kamada, Koki Ueno, Mikine Kume, Kouji Sakaguchi
Abstract Shift selection devices are desired to be flexible for design and layout, in order to realize the next generation of cockpits for Lexus vehicles. In addition, refined shift operation feelings are also required to be suitable for Lexus vehicles. To meet these demands, the Lexus LC500 has been equipped with a shift-by-wire system, which replaces the mechanical linkage between the shift selector and transmission with electrical signals and an actuator. This shift-by-wire system will be installed in a wide variety of Lexus powertrain lineup, including conventional gas vehicles and hybrid vehicles. Therefore, the next generation shift-by-wire system for Lexus has been developed with high reliability and applicability. This technology will be essential when autonomous driving and autonomous parking systems are realized in the near future.
2017-03-28
Technical Paper
2017-01-0917
Go Hayashita, Motoki Ohtani, Keiichiro Aoki, Shuntaro Okazaki
Abstract Exhaust systems must satisfy a wide range of requirements, including lowering emissions to comply with future fuel economy and emissions regulations. To help meet these requirements, new emissions control systems have been developed today. In addition, since air-fuel ratio (hereafter, A/F) control has a major impact on emissions, a new two-A/F sensor system with A/F sensors provided both upstream and downstream of the catalyst was developed, incorporating an A/F control capable of further lowering emissions with greater robustness. This development identified the hysteresis characteristics of the O2 sensor downstream of the catalyst as an important factor affecting emissions during conventional A/F control. Subsequently, reaction analysis was carried out using sensor reaction models and by evaluating sensors under real-world operating conditions.
2017-03-28
Journal Article
2017-01-0901
Alex Pink, Adam Ragatz, Lijuan Wang, Eric Wood, Jeffrey Gonder
Abstract Vehicles continuously report real-time fuel consumption estimates over their data bus, known as the controller area network (CAN). However, the accuracy of these fueling estimates is uncertain to researchers who collect these data from any given vehicle. To assess the accuracy of these estimates, CAN-reported fuel consumption data are compared against fuel measurements from precise instrumentation. The data analyzed consisted of eight medium/heavy-duty vehicles and two medium-duty engines. Varying discrepancies between CAN fueling rates and the more accurate measurements emerged but without a vehicular trend-for some vehicles the CAN under-reported fuel consumption and for others the CAN over-reported fuel consumption. Furthermore, a qualitative real-time analysis revealed that the operating conditions under which these fueling discrepancies arose varied among vehicles.
2017-03-28
Technical Paper
2017-01-0040
Michael Hafner, Thomas Pilutti
Abstract We propose a steering controller for automated trailer backup, which can be used on tractor-trailer configurations including fifth wheel campers and gooseneck style trailers. The controller steers the trailer based on real-time driver issued trailer curvature commands. We give a stability proof for the hierarchical control system, and demonstrate robustness under a specific set of modeling errors. Simulation results are provided along with experimental data from a full-size pickup truck and 5th wheel trailer.
2017-03-28
Technical Paper
2017-01-0041
Shengguang Xiong, Gangfeng Tan, Xuexun Guo, Longjie Xiao
Abstract Automotive Front Lighting System(AFS) can receive the steering signal and the vehicular speed signal to adjust the position of headlamps automatically. AFS will provide drivers more information of front road to protect drivers safe when driving at night. AFS works when there is a steering signal input. However, drivers often need the front road's information before they turn the steering wheel when vehicles are going to go through a sharp corner, AFS will not work in such a situation. This paper studied how to optimize the working time of AFS based on GIS (Geographic Information System) and GPS(Geographic Information System) to solve the problem. This paper analyzed the process of the vehicle is about to go through a corner. Low beams and high beams were discussed respectively.
2017-03-28
Technical Paper
2017-01-0039
Toshiya Hirose, Yasufumi Ohtsuka, Masato Gokan
Abstract A vehicle-to-vehicle communication system (V2V) sends and receives vehicle information by wireless communication and assists safe driving. The present study investigated the activation timings of collision information support, collision caution support, and collision warning support provided by a V2V in an experiment using a driving simulator for four situations of (1) assistance in braking, (2) assistance in accelerating, (3) assistance in making a right turn, and (4) assistance in making a left turn at a blind intersection. The four situations are common scenarios of traffic accidents in Japan. Safety margins for collision information support and collision warning support were the time required for the driver to fully apply the brake pedal, while the safety margin for collision caution support was the time required for the driver to begin applying the brake pedal. The study investigated the effects of adding safety margins to standard activation timings.
2017-03-28
Technical Paper
2017-01-0038
Corwin Stout, Milos Milacic, Fazal Syed, Ming Kuang
Abstract In recent years we have witnessed increased discrepancy between fuel economy numbers reported in accordance with EPA testing procedures and real world fuel economy reported by drivers. The debates range from needs for new testing procedures to the fact that driver complaints create one-sided distribution; drivers that get better fuel economy do not complain about the fuel economy, but only the ones whose fuel economy falls short of expectations. In this paper, we demonstrate fuel economy improvements that can be obtained if the driver is properly sophisticated in the skill of driving. Implementation of SmartGauge with EcoGuide into the Ford C-MAX Hybrid in 2013 helped drivers improve their fuel economy on hybrid vehicles. Further development of this idea led to the EcoCoach that would be implemented into all future Ford vehicles.
2017-03-28
Technical Paper
2017-01-0037
Xianyao Ping, Gangfeng Tan, Yahui Wu, Binyu Mei, Yuxin Pang
Abstract The drivers' hysteretic perception to surrounding environment will affect vehicular fuel economy, especially for the heavy-duty vehicles driving under complex conditions and long distance in mountainous areas. Unreasonable acceleration or deceleration on the slope will increase the fuel consumption. Improving the performance of the engine and the transmission system has limited energy saving potential, and most fuel-efficient driving assistant systems don't consider the road conditions. The main purpose of this research is to introduce an economic driving scheme with consideration of the prestored slope information in which the vehicle speed in mountainous slopes is reasonably planned to guide the driver's behavior for reduction of the fuel consumption. Economic driving optimization algorithm with low space dimension and fast computation speed is established to plan accurate and real-time economic driving scheme.
2017-03-28
Technical Paper
2017-01-0036
Michael Hafner, John Bales
Abstract We introduce a controller designed to stop a vehicle smoothly and accurately at a specified distance target, while being robust to unmeasured disturbances. This controller has a wide range of applications in instances where low speed longitudinal control of a vehicle is desired. Controller design was validated in a simulation using an ideal vehicle model based on first principles. Real world testing and tuning was performed on a full-size pickup truck to demonstrate controller performance.
2017-03-28
Technical Paper
2017-01-0035
Binyu Mei, Xuexun Guo, Gangfeng Tan, Yongbing Xu, Mengying Yang
Abstract Vehicle speed is an important factor to driving safety, which is directly related to the stability and braking performance of the vehicle. Besides, the precise measurement of the vehicle speed is the basis of some vehicle active safety systems. Even in the future intelligent transportation, high quality speed information will also play an important role. The commonly used vehicle speed measurement techniques are based on the wheel speed sensors, which are not accurate, especially when the wheels’ slip rate is not equal to zero. Focusing on these issues, image matching technology has been used to measure the vehicle speed in this paper. The image information of the road in the front of the vehicle is collected, and the pixel displacement of the vehicle is calculated by the matching system, thus accurately vehicle speed can be obtained. Compared with conventional speed measure technology, it has the advantages of wide measuring range, and high accuracy.
Viewing 271 to 300 of 16460