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Viewing 1 to 30 of 4523
2017-04-04
Event
Focusing on new theory, formulation and modeling of amplitude-, frequency- and temperature-dependent nonlinear components/systems such as mounts or bushings, shock absorbers, and joint friction/damping; dynamic characterization through lab and field testing; Linearization methodology; Model validation, application, and sensitivity analysis in vehicle system/subsystem simulations; Nonlinear system identification, modeling, and application in testing accuracy improvement, etc.
2017-04-04
Event
The focus of this session are the tests and test methods employed in the evaluation of the performance and durability of powertrain (engines, transmissions), driveline (4WD systems, driveshafts, axles), chassis (frame, suspensions, brakes, etc.) and body components, subsystems, and full vehicle systems.
2017-04-04
Event
The focus of this session are the tests and test methods employed in the evaluation of the performance and durability of powertrain (engines, transmissions), driveline (4WD systems, driveshafts, axles), chassis (frame, suspensions, brakes, etc.) and body components, subsystems, and full vehicle systems.
2017-03-28
Technical Paper
2017-01-1028
Daniel Bharathy, Ganesh Paramasivam
Venting for a diesel tank is an essential requirement to keep the tank stable by breathing in during suction & breathing out the excess pressure created inside because of vaporization. Vent valves with inappropriate specs affects the rate of supply of fuel during vacuum built up of pressure resulting in tank explosion or causes damage to the user during filling. Capacity of the tank, ambient temperature, environment, Return line temperature and application are the factors contribute in finalizing the venting specification. Considering these factors, study has been done on a metal & plastic fuel tank for a commercial vehicle application. Venting specification has been finalized for both plastic & metal tanks analytically. Vent valves developed and validated to meet the functional & durability requirements.
2017-03-28
Technical Paper
2017-01-0389
Carlo Cantoni, Giampiero Mastinu, Massimiliano Gobbi, Federico Ballo, Giorgio Previati
The durability performance of brake hoses is a crucial issue for such components. Accelerated fatigue testing of brake hoses is necessary for understanding achievable lifetime, actually computation is quite cumebersome due to the many different materials the hoses are made from. Despite SAE standards are available, accelerated testing of brake hoses subject to actual torsional and bending stresses seem important to provide relevant feedback to designers. In this paper, an innovative methodology for assessing the fatigue behaviour of brake hoses of road vehicles is proposed. A dynamic testbed is specifically designed and realised, able to reproduce the actual assembly conditions of the hoses fitted into a vehicle suspension. The designed testbed allows to replicate actual loading conditions on the brake hoses by simulating the vertical dynamics and steering of the suspension system together with brake pressure.
2017-03-28
Technical Paper
2017-01-0393
Keunsoo Kim
The fuel tank should keep the fuel stably at any vehicle driving condition but sometimes, the fuel tank can’t store fuel stably due to crack because the vehicle is driven at the various environmental conditions . In case of extreme hot ambient driving condition, the fuel tank pressure is increased because of fuel boiling. In case of normal ambient temperature, before fuel boiling and large engine purge condition. The fuel tank pressure is decreased. The repetitive excessive fuel tank pressure change will lead to damage the fuel tank. The fuel tank crack can lead to fuel leakage from the fuel tank that can lead to damage the vehicle such as fire. Until now, the analysis results of the fuel tank crack is the negative pressure due to engine purge and the decreased canister venting performance because of the dust, so canister venting performance have be improved but the fuel tank crack have not been solved.
2017-03-28
Technical Paper
2017-01-1154
Jimmy Kapadia, Thomas Gee, Alan Dona, Ming Kuang, Mark Jennings, Brandon Masterson, Daniel Kok, Chuck Wagner, Richard Isaacs
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
Technical Paper
2017-01-1170
Chen Wang, Tong Zhang, Wentai zhou
With the compound power-split transmission directly connected to engine in hyrbid vehicle, dramatic fluctuation of engine output torque resulted in strong jerks during mode transition from electric driving mode to hybrid driving mode. In order to enhance ride comfort and reduce the toruque gap during mode transition process, a coordinated control strategy is developed by taking well use of the engine, two motors, and wet brake clutch. Firstly, the mode transition process with clutch participation is described and analyzed. Secondly, engine output torque without combustion is modeled by utilizing the measured cylinder pumping pressure. And the dynamic model hybrid powertrain is deduced. Thirdly, a coordinated control strategy is designed to determine the desired motor torque, clutch torque, engine torque, and the moment of fuel injection. Active damping control with two degrees of freedom based on wheel speed observation is designed to mitigate the driveline speed oscillations.
2017-03-28
Technical Paper
2017-01-1147
Hyunjun Kim, Jingeon Kang, Dongsuk Kum
Input- and output-split hybrids, which use a single planetary gear (PG), have a good fuel economy, but a relatively low acceleration performance. In order to improve their acceleration performance, speed reduction gears (SRG) have been employed in various commercialized split hybrids. However, the full potential of using SRGs has not yet been investigated. In fact, adding one SRG to input- or output-split hybrids can improve not only their acceleration performance, but also their fuel economy. Nevertheless, the design space of input- and output-split configurations using one SRG is huge; 864 configurations are using two PGs connected through one interconnection and having one node grounded to a fixed platform. Thus, in order to solve this high computational load problem, an efficient comprehensive design methodology is highly required.
2017-03-28
Technical Paper
2017-01-0647
Bradley Denton, Christopher Chadwell, Raphael Gukelberger, Terrence Alger
The Dedicated EGR (D-EGR®) engine has shown improved efficiency and emissions while minimizing the challenges of traditional cooled EGR. The concept combines the benefits of cooled EGR with additional improvements resulting from in-cylinder fuel reformation. The fuel reformation takes place in the dedicated cylinder, which is also responsible for producing the diluents for the engine (EGR). The D-EGR system does present its own set of challenges. Because only one out of four cylinders is providing all of the dilution and reformate for the engine, there are three “missing” EGR pulses and problems with EGR distribution to all 4 cylinders exist. In testing, distribution problems were realized which led to poor engine operation. To address these spatial and temporal mixing challenges, a distribution mixer was developed and tested which improved cylinder-to-cylinder and cycle-to-cycle variation of EGR rate through improved EGR distribution.
2017-03-28
Technical Paper
2017-01-0405
Tianqi Lv, Xingxing Feng, Peijun Xu, Yunqing Zhang
Several constitutive models which capture the amplitude and frequency dependency of filled elastomers are implemented for the conventional engine mounts of automotive powertrain mounting system (PMS). Firstly, a multibody dynamic model of a light duty truck is proposed, which includes 6 degrees of freedom (DOFs) for the PMS. Secondly, several constitutive models for filled elastomers are implemented for the engine mounts of the PMS, including nonlinear elastic model, frictional derivative viscoelastic model, general Maxwell chains, Coulomb-type friction, Berg’s friction model, common Kelvin-Voigt model etc. The nonlinear behavior of dynamic stiffness and damping of the mounts are investigated. Thirdly, simulations of engine vibration dynamics are presented and compared with these models and the difference between common Kelvin-Voigt model and other constitutive models are observed and analyzed.
2017-03-28
Technical Paper
2017-01-0402
Zhigang Zhang, Shi Xiaohui, Ye Bin
Based on the formation mechanism of engaging force of clutch, the engagement was divided into four stages: idle travel stage, cushion spring stage, diaphragm spring stage and locking stage, and mechanism of transmitted torque in each stage was analyzed and the transmitted torque model of clutch was deduced. Multi-load step analysis method based on finite element was used to analyze the coupling load-deformation characteristics of diaphragm spring and cushion spring in engagement, and the change laws of engaging force, diaphragm spring force and release bearing force were achieved and their coupling interaction were studied. And then change of friction coefficient of clutch with oscillating temperature was measured on friction test rig, and effect of temperature on transmitted torque was further discussed. Finally, simulation results of transmitted torque were validated by the experiment. Results indicate that the transmitted torque in clutch engagement has a nonlinear characteristic.
2017-03-28
Technical Paper
2017-01-1356
Rainer Neumann
In the last years we recognize a big amount of innovative solutions in the field of automotive lighting and especially in front lighting systems. The major target to improve the light performance and to make driving at night safe is most important. The measure to for the performance rating and the ability to compare different systems with a technology neutral process seems to be quite difficult. The legislation is looking for a simplification with clearly defined parameters for the future. Experimental test series recently published causing a lot of discussions as the sensitivity of the aiming of the headlamps can cause completely different performance test results. The paper will report on a study with various production vehicles, all in the same way initially aimed and prepared for all type of technologies.
2017-03-28
Technical Paper
2017-01-0777
Gordon McTaggart-Cowan, Jian Huang, Sandeep Munshi
Late-cycle direct injection of natural gas allows a diesel-like combustion but with a significant reduction in CO2 emissions. High pressure direct injection (HPDI) technology uses a small diesel injection to ignite a non-premixed natural gas jet. This paper evaluates the impacts of changes in natural gas composition on the performance of a heavy-duty HPDI engine and on the implementation of a novel accelerometer-based sensor system to correct for the changes in fuel composition. The composition of natural gas varies significantly depending on source, suppliers, and seasons; this can significantly impact engine performance through changing both its auto-ignition properties (knocking propensity) and its energy content. For HPDI, unlike premixed charge engines, the main sensitivity is to energy density; the knocking potential of the fuel is not a significant barrier.
2017-03-28
Technical Paper
2017-01-0863
Bader Almansour, Sami Alawadhi, Subith Vasu
One of the most promising platforms for cellulosic biofuel generation is to harness the metabolic processes of endophytic fungi that directly convert lignocellulosic material into a variety of volatile organic compounds. The biofuel co-development framework was initiated at Sandia National Labs. Here, the synthetic biologists develop and engineer a new platform for drop-in fuel production from lignocellulosic biomass, using several endophytic fungi including Hypoxylon CI-4A, CO27-A, and Daldinia EC-12. Hence this process has the potential advantage that expensive pretreatment and fuel refining stages can be optimized thereby allowing scalability and cost reduction-two major considerations for widespread biofuel utilization. Large concentrations of ketones along with other volatile organic compounds (VOC’s) were produced by Hypoxylon CO27-A grown over swtichgrass media.
2017-03-28
Technical Paper
2017-01-0781
Philip Zoldak, Jeffrey Naber
In recent years, natural gas has been considered a replacement for diesel fuel in large bore engines, due to its low cost, high heating value and widespread availability. Stoichiometric premixed spark-ignition (SI), defined as port-fuel injection (PFI) of natural gas (NG) followed by SI close to top dead center (TDC), has traditionally been used as the main fuel delivery and combustion method for light and medium duty engines. However, premixed SI of NG results in inefficiencies in the intake process and combustion that is knock limited as boost and load are increased. Traditionally, high knock is addressed by spark timing retard. Spark timing retard can lead to misfires and low brake mean effective pressures. Thus premixed SI has limited low load use in heavy duty where compression ignition of diesel fuel remains dominant.
2017-03-28
Technical Paper
2017-01-0738
Akhilendra Pratap Singh, Avinash Kumar Agarwal
Premixed charge compression ignition (PCCI) combustion has the potential to utilise alternative fuels such as alcohols. PCCI combustion emits significantly lower oxides of nitrogen (NOx) and particulate matter (PM) and resulted thermal efficiency similar to conventional CI engines. However, PCCI combustion cannot be used in production grade engines due to its incapability to operate at high engine loads. This study focussed on development of hybrid combustion engine, which can operate in both combustion modes such as CI combustion as well as PCCI combustion mode. Hybrid combustion system was controlled by an open ECU, which varied the fuel injection parameters for mode switching between CI and PCCI combustion modes. At low-to-medium engine loads, engine was operated in PCCI combustion mode and at higher engine loads ECU automatically switched the engine operation in CI combustion mode.
2017-03-28
Technical Paper
2017-01-1226
Nurani Chandrasekhar, Chun Tang, Natee Limsuwan, Jacob Krizan, Zhichun Ma, Joel Hetrick PhD, Wei Wu
Noise and Vibration signature of an electric machine is an outcome of complex interaction between various source level disturbances like torque ripple and radial magnetic force and the surrounding structure to which the motor is attached. These can be radiated directly from the motor housing and also can be transmitted through the structural attachments (stator bolts, mounts etc.). The stator excitation current is not perfectly sinusoidal but contains different levels of harmonics. Harmonics impact Torque ripple, which in turn could translate into undesirable Motor noise. This paper addresses the impact of torque ripple on Motor whine noise. In this work, the electric machine torque ripple was computed based on the stator current that was measured during Motor dyno testing at prescribed torque and speed levels. The Motor NVH under specific torque levels was measured through testing in an anechoic transmission dynamometer cell.
2017-03-28
Technical Paper
2017-01-0865
Mark Walls, Michael Joo, Michael Ross
Liquefied petroleum gas (LPG) is commonly known as autogas when used as a fuel for internal combustion engines. Autogas is primarily made up of propane, but can contain small amounts of butane, methane and propylene. Autogas is not a new fuel for internal combustion engines, but as engine technology evolves, the properties of autogas can be utilized to improve engine and vehicle efficiency. With support from the Propane Education & Research Council (PERC), Southwest Research Institute (SwRI) performed testing to quantify efficiency differences with liquid autogas direct injection in a modern downsized and boosted direct-injected engine using the production gasoline fuel injection hardware. Engine dynamometer testing demonstrated that autogas produced similar performance characteristics to gasoline at part load, but could be used to improve brake thermal efficiency at loads above 12 bar BMEP.
2017-03-28
Technical Paper
2017-01-1245
Takamitsu Tajima
Reducing the amount of CO2 emissions to zero while driving is considered an important goal for the mobility sector in order to achieve a zero CO2 society. A key point in achieving this is the further evolution of electrified vehicles that are driven only by motors and are not equipped with a generator that uses fossil fuels, that is to say electric vehicles (EV) and fuel cell vehicles (FCV). Major issues facing EV include range, charging (hassle, time, construction of infrastructure), and reduced driving performance due to increased vehicle weight. Technology enabling to both supply power and perform charging while driving (dynamic charging) is being researched and developed as a means of addressing issues such as those above.
2017-03-28
Technical Paper
2017-01-0391
Daniel Meyer, Peter Maehling, Thomson Varghese, Jeffery Lewis
Precise and accurate engine internal combustion pressure measurements are typically built upon extremely low level piezoelectric sensor signals acquired in the laboratory. In turn, these minute signals must be conditioned accurately by electronic charge amplifiers then processed for meaningful analysis. Laboratory standard operating procedures often overlook the importance of timely and rigorous calibration of the equipment using sufficient environmental controls. In some facilities, years have been allowed between metrology-quality calibrations, introducing the potential for significant out-of-tolerance conditions and non-compliance to accredited measurement standards. Accurate and timely calibration supports the validity of using combustion data in engine design decisions, as well as avoiding development program timing delays, when additional unplanned testing becomes required.
2017-03-28
Technical Paper
2017-01-0392
Dae-Un Sung, James Busfield, Yong Hyun Ryu
The vehicle elastomeric components such as engine mounts are aged and degraded by environmental loads during long term usage. These make the degradation of vehicle driving performance comparing with a new condition. In this study, the degradation of NVH (Noise, Vibration and Harshness) of used vehicles was analyzed. The main cause could be identified by the analysis of elastomers’ vibration insulation property changes. The properties changes of aged engine mounts were analyzed and compared with initial properties. The accelerated laboratory aging test mode was developed for simulating the degradation of engine mounts. Moreover, parametric study was carried out. The engineering design parameters of elastomers such as volume, thickness and loading types were identified to improve the thermal aging phenomenon.
2017-03-28
Technical Paper
2017-01-0380
Liang Wang, Robert Burger, Alan Aloe
It occurs frequently that automotive components fail due to vibration excitations on the proving ground during their last phase of durability validation process. This leads to additional design release time, cost and even impact vehicle launch if a safety issue. The appearing cause of this issue is under-testing or lack of component level testing, however the root cause is that vibration fatigue is not considered during the design phase of the parts. This paper introduces aspects of vibration fatigues helping designer and release engineer better understand the requirements, testing methodologies available, and ideas for improving vibration fatigue for designing and validating their product. Several examples are given to introduce the fundamental but universal root cause of all the vibration fatigue failures. Typical vibration levels and frequency contents on varied area on automotive are introduced.
2017-03-28
Technical Paper
2017-01-0381
Karthik lakshminarayanan, Dinesh Kumar Rajappan, Prasanna Elizamoses, Srinivasa Chandra V
This abstract report on data acquisition procedure followed for a critical metal bumper to be used for a commercial application and consequently the validation methodology and defining the target duration based on life of the vehicle. Covariance is considered to be a major phenomenon in proving ground data acquisition and it is be maintained less than 0.05. In this project, importance of covariance in data acquisition studied before simulation of acquired data. In addition to that, multiple testing conditions like uni-axial and bi-axial carried out to achieve failure. Proving ground tracks data is used for bi-axial vibration test and constant spectrum signal of 5 Hz to 40 Hz & 3g acceleration is used for uni-axial vibration test. Target hours for uni-axial test (Z direction) are arrived using pseudo damage calculation which helps a lot in accelerating the test duration.
2017-03-28
Technical Paper
2017-01-1249
Masahiro Seguchi
Compact, high efficiency and high reliability is required for an xEV motor generator. IPM rotors with neodymium magnet are widely applied for xEV motors to achieve these requirements. However, the neodymium magnet material has a big impact on motor cost and there is supply chain risk due to increased usage of these rare earth materials for future automotive xEV’s. On the other hand, a wound-field rotor does not need magnets and can achieve equivalent performance to an IPM rotor. However, brushes are required in order to supply current to the winding coil of the rotor. This may cause insulation issues on xEV motors which utilize high voltage and high currents. Therefore, it can be suggested to develop a system which supplies electric energy to the rotor field winding coil from stator without brushes by applying a transformer between stator coil and rotor field winding. Specifically, add auxiliary magnetic poles between each field winding poles and wind sub-coils to these poles.
2017-03-28
Technical Paper
2017-01-0384
Shawn S. You
Due to the increasing pressure of shortened development cycles and the desire of saving costs, auto makers are increasingly using analysis tools to validate vehicle design and specify lab testing with less road load data acquisition. Virtual testing is a method that simulates lab testing using analysis software. This approach has been used more and more in vehicle design evaluation. The main advantages of this approach include that the design can be evaluated before a prototype is available and virtual testing results can be easily validated by subsequent physical testing. The combination of physical and virtual testing can accelerate the design process due to the identification and subsequent elimination of physical and virtual prototype deficiencies, such as transducer related errors and model parameter inaccuracies. This paper introduces a real virtual testing project.
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