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2015-04-14
Technical Paper
2015-01-1508
Lijiao Yu, Hongyu Zheng
Abstract As electric technique develops fast, steering system changes from conventional mechanic steering system to Hydraulic Power Steering (HPS). Flowing HPS, Electrically Controlled Steering (ECS) system, including Electric Power Steering (EPS) system, Active Front Steering (AFS) system and Steer-by-Wire (SBW) system. ECS makes it easy for a driver to control a steering wheel using a less torque at a low speed, which is usually called steering portability Besides, ECS could also help a driver steer a vehicle stably at a high speed, which is usually called steering stability ECS provides an optional method to solve the contradiction between steering portability and steering stability. [1] [2] The study of ECS involves mechanic design, detection of electric components, software design and so on. Researches of ECS need a lot of trials and errors. By now, the development of ECS mostly depends on experiments on Hardware-in-the- Loop (HIL) and real vehicles.
2015-04-14
Technical Paper
2015-01-1446
Timothy P. Austin, David P. Plant, Joseph E. LeFevre
Abstract The use of Heavy Vehicle Event Data Recorders (HVEDRs) in collision analysis has been well recognized in past research. Numerous publications have been presented illustrating data accuracy both in normal operating conditions as well as under emergency braking conditions. These data recording devices are generally incorporated into Electronic Control Modules (ECMs) for engines or Electronic Control Units (ECUs) for other vehicular components such as the Anti-Lock Brake System. Other research has looked at after-market recorders, including publically-available Global Positioning System (GPS) devices and fleet management tools such as Qualcomm. In 2009, the National Fire Protection Association (NFPA) incorporated a Vehicle Data Recorder (VDR) component into their Standard for Automotive Fire Apparatus. The purpose of this was to “…capture data that can be used to promote safe driving and riding practices.”
2015-04-14
Technical Paper
2015-01-1066
Frank Adam, Jan Schoenhaber, Armin Wagner
Abstract The introduction of vehicle emission and fuel economy standards (CO2) accelerates the introduction of new platform and powertrain combinations into the market place. All of these combinations will require unique exhaust gas aftertreatment systems that comply with the current emission legislation. The optimization of each unique aftertreatment solution requires the proper application of catalyst technologies at the lowest PGM concentrations. The optimization process needs to be fast, reliable, realistic and cost attractive. It is arguable that performing the aftertreatment optimization on a chassis dynamometer is variable, time consuming and expensive. This work demonstrates how a synthetic gas bench (SGB) can be used to simulate stoichiometric engine emissions and aftertreatment performance. The SGB procedure duplicates the vehicle NEDC engine-out emissions and catalyst heat-up profiles.
2015-04-14
Technical Paper
2015-01-0594
Xin Xie, Changqing Du, Xiaona Li, Yi-Hsin Chen, Guobiao Yang, Yongjun Zhou, Dajun Zhou, Yaqian Zheng, Bernard Sia, Christina Phillips, Lianxiang Yang
Abstract This paper introduces an industrial application of digital image correlation technique on the measurement of aluminum edge stretching limit. In this study, notch-shape aluminum coupons with three different pre-strain conditions are tested. The edge stretching is proceeded by standard MTS machine. A dual-camera 3D Digital Image Correlation (DIC) system is used for the full field measurement of strain distribution in the thickness direction. Selected air brush is utilized to form a random distributed speckle pattern on the edge of sheet metal. A pair of special optical lens systems are used to observe the small measurement edge area. From the test results, it demonstrate that refer to the notched coupon thickness, pre-tension does not affect the fracture limit; refer to the virgin sheet thickness, the average edge stretch thinning limits show a consistent increasing trend as the pre-stretch strain increased.
2015-04-14
Technical Paper
2015-01-1543
Petter Ekman, Roland Gårdhagen, Torbjörn Virdung, Matts Karlsson
Abstract Road transportation by trucks is the major part of the goods transportations system in the European Union (EU), and there is a need for increased fuel efficiency. While truck manufacturers already spend significant resources in order to reduce the emissions from their vehicles, most truck manufacturers do not control the shape of the trailer and/or swap bodies. These devices are usually manufactured by different companies that cannot consider the overall aerodynamics around the complete vehicle. By use of Computational Fluid Dynamics (CFD) and previous wind tunnel experiments, the flow around a simplified generic tractor-trailer model has been investigated. With better understanding of the flow features around the tractor with attached trailer or swap bodies, an improved design of the trailer and swap body can be achieved, which is the aim for the project.
2015-04-14
Technical Paper
2015-01-1562
Matts Karlsson, Roland Gårdhagen, Petter Ekman, David Söderblom, Claes Löfroth
Abstract There is a need for reducing fuel consumption and thereby also reducing CO2 and other emissions in all areas of transportation and the forest industry is no exception. In the particular case of timber trucks special care have to be taken when designing such vehicles; they have to be sturdy and operate in harsh conditions and they are being driven empty half the time. It is well known that the aerodynamic resistance constitutes a significant part of the vehicles driving resistance and four areas in particular, front of vehicle, gap, side/underbody and rear of the vehicle contributes about one quarter each. In order to address these issues a wind tunnel investigation was initiated where a 1:6 scale model of a timber truck was designed to operate in a 3.6 m wind tunnel. The present model resembles a generic timber truck with a flexible design such that different configurations could be tested easily.
2015-04-14
Journal Article
2015-01-0680
Rong Zhang, Qian Zou, Gary Barber, Ben Zhou, Yucong Wang
Abstract In practice, the piston wrist pin is either fixed to the connecting rod or floats between the connecting rod and the piston. The tribological behavior of fixed wrist pins have been studied by several researchers, however there have been few studies done on the floating wrist pin. A new bench rig has been designed and constructed to investigate the tribological behavior between floating pins and pin bore bearings. The experiments were run using both fixed pins and floating pins under the same working conditions. It was found that for fixed pins there was severe damage on the pin bore in a very short time (5 minutes) and material transfer occurs between the wrist pin and pin bore; however, for the floating pin, even after a long testing time (60 minutes) there was minimal surface damage on either the pin bore or wrist pin.
2015-04-14
Journal Article
2015-01-0357
Huize Li, Predrag Hrnjak
Abstract This paper presents a method of utilizing infrared images to quantify the distribution of liquid refrigerant mass flow rate in microchannel heat exchangers, which are widely used in automobile air conditioning systems. In order to achieve quantification, a relationship is built between the liquid mass flow rate through each microchannel tube and the corresponding air side capacity calculated from the infrared measurement of the wall temperature. After being implemented in a heat exchanger model, the quantification method is validated against experimental data. This method can be used for several types of heat exchangers and it can be applied to various heat exchanger designs.
2015-04-14
Journal Article
2015-01-0488
Andreea Elena Balau, Dennis Kooijman, Ignacio Vazquez Rodarte, Norbert Ligterink
Abstract This paper presents a methodology and tool that stochastically generates drive cycles based on measured data, with the purpose of testing and benchmarking light duty vehicles in a simulation environment or on a test-bench. The WLTP database, containing real world driving measurements, was used as input data. Consequently cycles that contain typical accelerations per velocity and road types are generated, such that these cycles are representative to real driving behavior. The stochastic drive cycle generator is developed in Matlab and is based on Markov processes. Two separate stochastic generators are used: one for generating the road type and one for generating the vehicle acceleration. First, a random road type profile is generated from the four different road types that are considered in the WLTP database: urban, rural, motorway and high-motorway, each of them with sub-road types based on different velocity bins.
2015-04-14
Journal Article
2015-01-0489
Jason Rogers
Abstract A 3D-and-Excel-based predictive tool was developed to determine trunk spring movement for preventing recurrence of a noise problem. While effective, the tool could not completely explain measured results on the completed body unit (CBU). Since design data is used as the input, it was hypothesized that the difference between predicted and actual results was related to tolerance variation on the actual vehicle. Using Siemens® Variation Analysis software, the CBU was built and simulated virtually with tolerances using a Monte Carlo model. The study found that the hypothesis was correct; tolerance variation was fully responsible for the differences. In addition, the study also allowed accurate prediction of failure rates.
2015-04-14
Journal Article
2015-01-0528
Armin Abedini, Cliff Butcher, David Anderson, Michael Worswick, Timothy Skszek
Abstract Two different shear sample geometries were employed to investigate the elastoplastic and failure behaviour of three automotive alloy rolled sheets; a highly anisotropic magnesium alloy (ZEK100) and two relatively isotropic dual phase steels (DP600 and DP780). The performance of the so-called butterfly type specimen (Mohr and Henn 2007, Dunand and Mohr 2011) was evaluated at quasi-static conditions along with the shear geometry of Peirs et al. (2012) using in situ 3-D digital image correlation (DIC) strain measurement techniques. It was shown that both test geometries resulted in similar trends of the load-displacement response; however, the fracture strains obtained using the butterfly specimen were lower for the ZEK100 and DP780. It was demonstrated that the ZEK100 exhibits strong anisotropy in terms of the shear work hardening rate and failure strain.
2015-04-14
Journal Article
2015-01-0556
Wenkai Li, Haitao Cui, Weidong Wen, Xuming Su, Carlos Engler-Pinto
Abstract Ultrasonic fatigue tests (testing frequency around 20 kHz) have been conducted on four different cast aluminum alloys each with a distinct composition, heat treatment, and microstructure. Tests were performed in dry air, laboratory air and submerged in water. For some alloys, the ultrasonic fatigue lives were dramatically affected by the environment humidity. The effects of different factors like material composition, yield strength, secondary dendrite arm spacing and porosity were investigated; it was concluded that the material strength may be the key factor influencing the environmental humidity effect in ultrasonic fatigue testing. Further investigation on the effect of chemical composition, especially copper content, is needed.
2015-04-14
Journal Article
2015-01-0589
Andrew Moskalik, Paul Dekraker, John Kargul, Daniel Barba
Abstract The benchmarking study described in this paper uses data from chassis dynamometer testing to determine the efficiency and operation of vehicle driveline components. A robust test procedure was created that can be followed with no a priori knowledge of component performance, nor additional instrumentation installed in the vehicle. To develop the procedure, a 2013 Chevrolet Malibu was tested on a chassis dynamometer. Dynamometer data, emissions data, and data from the vehicle controller area network (CAN) bus were used to construct efficiency maps for the engine and transmission. These maps were compared to maps of the same components produced from standalone component benchmarking, resulting in a good match between results from in-vehicle and standalone testing. The benchmarking methodology was extended to a 2013 Mercedes E350 diesel vehicle. Dynamometer, emissions, and CAN data were used to construct efficiency maps and operation strategies for the engine and transmission.
2015-04-14
Journal Article
2015-01-0595
T. Mathialakan, V. U. Karthik, Paramsothy Jayakumar, Ravi Thyagarajan, S. Ratnajeevan H. Hoole
Abstract This paper presents a computational investigation of the validity of eddy current testing (ECT) for defects embedded in steel using parametrically designed defects. Of particular focus is the depths at which defects can be detected through ECT. Building on this we characterize interior defects by parametrically describing them and then examining the response fields through measurement. Thereby we seek to establish the depth and direction of detectable cracks. As a second step, we match measurements from eddy current excitations to computed fields through finite element optimization. This develops further our previously presented methods of defect characterization. Here rough contours of synthesized shapes are avoided by a novel scheme of averaging neighbor heights rather than using complex Bézier curves, constraints and such like. This avoids the jagged shapes corresponding to mathematically correct but unrealistic synthesized shapes in design and nondestructive evaluation.
2015-04-14
Journal Article
2015-01-0599
Akhilendra Pratap Singh, Aditya Gupta, Avinash Kumar Agarwal
Abstract Better understanding of flow phenomena inside the combustion chamber of a diesel engine and accurate measurement of flow parameters is necessary for engine optimization i.e. enhancing power output, fuel economy improvement and emissions control. Airflow structures developed inside the engine combustion chamber significantly influence the air-fuel mixing. In this study, in-cylinder air flow characteristics of a motored, four-valve diesel engine were investigated using time-resolved high-speed Tomographic Particle Imaging Velocimetry (PIV). Single cylinder optical engine provides full optical access of combustion chamber through a transparent cylinder and flat transparent piston top. Experiments were performed in different vertical planes at different engine speeds during the intake and compression stroke under motoring condition. For visualization of air flow pattern, graphite particles were used for flow seeding.
2015-04-14
WIP Standard
J2938
This SAE Recommended Practice provides test procedures, requirements, and guidelines for the methods of the measurement of lumen maintenance of LED devices (packages, arrays and modules). This document does not provide guidance or make any recommendation regarding predictive estimations or extrapolation for lumen maintenance beyond the limits of the lumen maintenance determined from actual measurements.
2015-04-14
Journal Article
2015-01-1478
Michelle Heller, Sarah Sharpe, William Newberry, Alan Dibb, John Zolock, Jeffrey Croteau, Michael Carhart, Jason Kerrigan, Mark Clauser
Abstract Occupant kinematics during rollover motor vehicle collisions have been investigated over the past thirty years utilizing Anthropomorphic Test Devices (ATDs) in various test methodologies such as dolly rollover tests, CRIS testing, spin-fixture testing, and ramp-induced rollovers. Recent testing has utilized steer maneuver-induced furrow tripped rollovers to gain further understanding of vehicle kinematics, including the vehicle's pre-trip motion. The current study consisted of two rollover tests utilizing instrumented test vehicles and instrumented ATDs to investigate occupant kinematics and injury response throughout the entire rollover sequences, from pre-trip vehicle motion to the position of rest. The two steer maneuver-induced furrow tripped rollover tests utilized a mid-sized 4-door sedan and a full-sized crew-cab pickup truck. The pickup truck was equipped with seatbelt pretensioners and rollover-activated side curtain airbags (RSCAs).
2015-04-14
Technical Paper
2015-01-1477
Robert Larson, Jeffrey Croteau, Cleve Bare, John Zolock, Daniel Peterson, Jason Skiera, Jason R. Kerrigan, Mark D. Clauser
Abstract Extensive testing has been conducted to evaluate both the dynamic response of vehicle structures and occupant protection systems in rollover collisions though the use of Anthropomorphic Test Devices (ATDs). Rollover test methods that utilize a fixture to initiate the rollover event include the SAE2114 dolly, inverted drop tests, accelerating vehicle body buck on a decelerating sled, ramp-induced rollovers, and Controlled Rollover Impact System (CRIS) Tests. More recently, programmable steering controllers have been used with sedans, vans, pickup trucks, and SUVs to induce a rollover, primarily for studying the vehicle kinematics for accident reconstruction applications. The goal of this study was to create a prototypical rollover crash test for the study of vehicle dynamics and occupant injury risk where the rollover is initiated by a steering input over realistic terrain without the constraints of previously used test methods.
2015-04-14
Journal Article
2015-01-0636
Yu Zhang, Lifu Wang, Bangji Zhang, Nong Zhang
Abstract Effectively obtaining physical parameters for vehicle dynamic model is the key to successfully performing any computer-based dynamic analysis, control strategy development or optimization. For a spring and lump mass vehicle model, which is a type of vehicle model widely used, its physical parameters include sprung mass, unsprung mass, inertial properties of the sprung mass, stiffness and damping coefficient of suspension and tire, etc. To minimize error, the paper proposes a method to estimate these parameters from vehicle modal parameters which are in turn obtained through full-car dynamic testing. To verify its effectiveness, a visual vehicle with a set of given parameters, build in the Adams(Automatic Dynamic Analysis of Mechanical Systems)/Car environment, is used to perform the dynamic testing and provide the testing data for the parameter estimation.
2015-04-14
Journal Article
2015-01-0834
Mark Sellnau, Wayne Moore, James Sinnamon, Kevin Hoyer, Matthew Foster, Harry Husted
Abstract A 1.8L Gasoline Direct Injection Compression Ignition (GDCI) engine was tested over a wide range of engine speeds and loads using RON91 gasoline. The engine was operated with a new partially premixed combustion process without combustion mode switching. Injection parameters were used to control mixture stratification and combustion phasing using a multiple-late injection strategy with GDi-like injection pressures. At idle and low loads, rebreathing of hot exhaust gases provided stable compression ignition with very low engine-out NOx and PM emissions. Rebreathing enabled reduced boost pressure, while increasing exhaust temperatures greatly. Hydrocarbon and carbon monoxide emissions after the oxidation catalyst were very low. Brake specific fuel consumption (BSFC) of 267 g/kWh was measured at the 2000 rpm-2bar BMEP global test point.
2015-04-14
Journal Article
2015-01-1557
Reinhard Blumrich, Nils Widdecke, Jochen Wiedemann, Armin Michelbach, Felix Wittmeier, Oliver Beland
Abstract For many years FKFS has operated the full-scale aeroacoustic wind tunnel of University of Stuttgart. To keep this wind tunnel as one of the most modern ones of its kind, it has again been upgraded significantly. The upgrade improved the aerodynamic as well as the aeroacoustic performance and accelerated the operational processes. Additionally, new innovative features have significantly enlarged the test capabilities. A new patented, modular belt system (FKFS first®) allows high performance measurements for race cars in a 3-belt mode as well as efficient measurements for production vehicle development in a 5-belt mode. The belt system is accompanied by a new, larger turntable and a new under-floor balance which enables high-accuracy measurements of forces and moments also for a high resolution in time. For the elimination of parasitic forces generated at the wheel drive units, a specific correction procedure has been implemented, which is patented, too (FKFS pace®).
2015-04-14
Journal Article
2015-01-1672
Clemens Biet, Roland Baar
Abstract Acoustic measurements, especially interesting for new bearing concepts such as ball bearings, are an important part of the evaluation of turbochargers. Typically, acoustic benchmarking is done at standard conditions, neglecting possible negative effects of very low temperatures, as they might be encountered in real-world applications. For realistic turbocharger measurements at cold environment conditions down to −10 °C, special adjustments to the turbocharger test bench have been made. This article introduces a soundproofed climate chamber built in the turbocharger test bench which is able to achieve low component and oil supply temperatures while still providing adequate conditions for acoustic measurements. In the first part of the paper, the concept of the acoustic climate chamber is presented. Layout calculations are shown as an indicator for the performance of the acoustic and thermal isolation.
2015-04-14
Journal Article
2015-01-1697
Daniel Freudenhammer, Brian Peterson, Carl-Philipp Ding, Benjamin Boehm, Sven Grundmann
Abstract Magnetic Resonance Velocimetry (MRV) measurements are performed in 1:1 scale models of a single-cylinder optical engine to investigate the differences in the inlet flow due to geometrical changes of the cylinder head. The models are steady flow water-analogue of the optical IC engine with a fixed valve lift of 9.21 mm to simulate the induction flow at 270° bTDC. The applicability of MRV to engine flows despite the differences in experimental operating parameters between the steady flow model and the optical IC engine are demonstrated and well addressed in this manuscript and in a previous work [1]. To provide trust into the MRV measurements, the data is validated with phase-averaged particle image velocimetry (PIV) measurements performed within the optical engine. The main geometrical changes between the cylinder heads include a variation of intake valve diameter and slight modifications to the exit of the intake port.
2015-04-14
Journal Article
2015-01-0647
Rafael Fietzek, Stephan Rinderknecht
Abstract During the last years mechatronic systems developed into one of the biggest drivers of innovation in the automotive industry. The start of production of systems like dual clutch transmission, lane departure warning systems and active suspensions proves this statement. These systems have an influence on the longitudinal, steering and vertical dynamics of the vehicle. That is why the interaction on vehicle level is crucial for an optimal result in the fields of efficiency, comfort, safety and dynamics. To optimize the interaction of mechatronic systems, in this paper a new test rig concept for a complete vehicle is presented. The so-called Car-in-the-Loop-concept is capable of realistically reproducing the loads, which act on the powertrain, the steering and the suspension during a test drive.
2015-04-14
Journal Article
2015-01-1061
Piotr Bielaczyc, Andrzej Szczotka, Joseph Woodburn
Abstract The aim of this paper was to explore the influence of CNG fuel on emissions from light-duty vehicles in the context of the new Euro 6 emissions requirements and to compare exhaust emissions of the vehicles fueled with CNG and with gasoline. Emissions testing was performed on a chassis dynamometer according to the current EU legislative test method, over the New European Driving Cycle (NEDC). Additional tests were also performed on one of the test vehicles over the World Harmonized Light Vehicles Test Cycle (WLTC) according to the Global Technical Regulation No. 15 test procedure. The focus was on regulated exhaust emissions; both legislative (CVS-bag) and modal (continuous) analyses of the following gases were performed: CO (carbon monoxide), THC (total hydrocarbons), CH4 (methane), NMHC (non-methane hydrocarbons), NOx (oxides of nitrogen) and CO2 (carbon dioxide).
2015-04-14
Journal Article
2015-01-1342
Christoph Huber, Bernhard Weigand, Heinrich Reister, Thomas Binner
Abstract A physically based model to predict the amount of snow which is entering the air intake of an automobile is extremely important for the automotive industry. It allows to improve the air intake system in the development state so that new vehicles can be developed in a shorter time. Using an Eulerian/Lagrangian approach within a commercial CFD-software we set up a model and calculated the snow ingress into an air intake of an automobile. In our numerical investigations we considered different particle shapes when calculating the drag coefficient, different coefficients of restitution and different particle sizes. Furthermore two-way coupling was considered. To obtain key parameters for the simulation, we measured the size of snow particles in the Daimler climatic wind tunnel in Sindelfingen by using a microscope and a measuring device from Malvern. Besides we used mechanical snow traps to determine the snow mass flux in the climatic wind tunnel and on a test area in Sweden.
2015-04-14
Journal Article
2015-01-1381
Jason P. Huczek, R. Rhoads Stephenson
Abstract The Department of Transportation (DOT) National Highway Traffic Safety Administration (NHTSA) awarded a contract to Southwest Research Institute (SwRI) to conduct research and testing in the interest of motorcoach fire safety. The goal of this program was to develop and validate procedures and metrics to evaluate current and future detection, suppression, and exterior fire-hardening technologies that prevent or delay fire penetration into the passenger compartment of a motorcoach - in order to increase passenger evacuation time. The program was initiated with a literature review and characterization of the thermal environment of motorcoach fires and survey of engine compartments, firewalls, and wheel wells of motorcoaches currently in North American service. These characterizations assisted in the development of test methods and identification of the metrics for analysis.
2015-04-14
Journal Article
2015-01-1517
David Stalnaker, Ke-Jun Xie, Terence Wei
Abstract Tire manufacturers need to perform various types of testing to determine tire performance under representative vehicle load conditions. However, test results are influenced by a number of external variables other than tire construction. Vehicle load distribution and suspension properties are some of those external variables which can have a significant effect on tire wear rate and durability. Therefore, in order to measure real world tire performance in a controlled and repeatable manner, a representative vehicle and associated tire load conditions are needed. Laboratory or indoor tire testing offers many advantages over vehicle fleet testing. It provides a well-defined test environment and repeatable results without influence from external factors. Indoor testing has been largely developed around the process of simulating tire wear performance on a specific reference vehicle, including its specific weight distribution, suspension characteristics, and alignment.
2015-04-14
Journal Article
2015-01-1525
Rocky Khasow, Scott Best, Martin Agelin-Chaab, John Komar, Gary Elfstrom
Abstract Underbody vehicle flows are poorly understood given the comparatively small field of research to draw upon; even more so in the case of crosswinds. With the advent of electric and hybrid electric vehicles and their increased cooling demands, there is a need for a link between the aerodynamic flow field and the thermodynamic response. Thus underbody research considering a yawing vehicle was conducted on a Chevrolet Aveo5 hatchback. The vehicle was outfitted with a heat source to provide a baseline analysis along thermocouples, pressure probes and flow visualization tufts. The climatic wind tunnel at the University Of Ontario Institute Of Technology's Automotive Centre of Excellence provided video data of the tufts and thermal imaging data of the heat source.
2015-04-14
Journal Article
2015-01-1530
Todd Lounsberry, Joel Walter
Abstract In recent years, there has been renewed attention focused on open jet correction methods, in particular on the two-measurement method of E. Mercker, K. Cooper, and co-workers. This method accounts for blockage and static pressure gradient effects in automotive wind tunnels and has been shown by both computations and experiments to appropriately adjust drag coefficients towards an on-road condition, thus allowing results from different wind tunnels to be compared on a more equitable basis. However, most wind tunnels have yet to adopt the method as standard practice due to difficulties in practical application. In particular, it is necessary to measure the aerodynamic forces on every vehicle configuration in two different static pressure gradients to capture that portion of the correction.
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