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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
2017-01-0764
Gabriele Di Blasio, Giacomo Belgiorno, Carlo Beatrice
The paper reports the results of a wide experimental campaign aimed to assess the effects of the geometric compression ratio variation on the performance of light-duty diesel engines operated in dual-fuel NG-diesel mode in terms of fuel consumption, NVH and pollutant emissions. The single-cylinder research engine employed in the experimental campaign had a combustion system is representatives of a 2L automotive diesel engine for passenger cars. The test methodology was defined in order to analyse carefully the effects of the compression ratio, injection parameters and air throttling on the global performances and emissions, also in terms of emitted carbonaceous particles. Three pistons with different bowl volumes corresponding to compression ratio (CR) values of 16.5, 15.5 and 14.5 were selected for the whole test campaign.
2017-03-28
Technical Paper
2017-01-0341
Seyyedvahid Mortazavian, Javid Moraveji, Reda Adimi, Xingfu Chen
Engine camshaft cap components experience high number of fluctuating loads during engine operation. The problem is complicated in engines with variable cam timing, because the loading for these components are sensitive to engine valve timing (combustion phasing) which can lead to catastrophic overload or fatigue failures. Improving the design of these components using computer-aided tools can drastically reduce the cost and time to the market of the final acceptable design, by eliminating the number of physical prototypes. Hence, a decent and robust finite element analysis with representative load and boundary conditions can significantly reduce the premature failures in engine development. In this study, first a finite element analysis method is developed for simulating a cap punching bench test. Effect of punch radius and shape on the component stiffness is investigated and correlated with test data.
2017-03-28
Technical Paper
2017-01-1676
Hartmut Lackner
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 investigate the cost drivers of testing multivariable systems and define novel criteria to systematically sample variants for the purpose of testing. The presented criteria reduce the test effort by means of tested variants as well as executed test steps.
2017-03-28
Technical Paper
2017-01-0371
Raju Gandikota, Amit Nair, Kurt Miller
Testing elastomeric materials that undergo large strains pose challenges especially when establishing failure criteria. The failure criterion for composites and polymers based on finite elasticity published byFeng (1) requires testing under uni-axial and bi-axial stretching modes. The classic inflation of a circular disk for bi-axial stretch mode poses stability and safety challenges. The test can also be sensitive to end constraints resulting in failure of materials at the constraints. Bi-axial stretching with a hemispherical punch is explored in this work. The bi-axial stretching allows controlled and repeatabletesting. It establishes clear and reliable failure mechanism of the material at the poles. Through a combination of testing and numerical methods, the stretch ratios and its relation to failure has been established.
2017-03-28
Technical Paper
2017-01-1259
Eduardo D. Marquez, John Stevenson, Ethan Dietrich, Douglas Nelson, Christopher Flake, Alexander Neblett, Samuel Reinsel
The Hybrid Electric Vehicle Team of Virginia Tech (HEVT) is modeling and testing powertrain components for a parallel plug-in hybrid electric vehicle (PHEV). The custom powertrain is being implemented in a 2016 Chevrolet Camaro for EcoCAR 3. The engine, a General Motors (GM) L83 5.3L V8 with Active Fuel Management (AFM) from a 2014 Silverado, is of particular importance for vehicle integration and functionality. The engine is one of two torque producing components in the powertrain. AFM allows the engine to deactivate four of the eight cylinders which is essential to meet competition goals to reduce petroleum energy use and greenhouse gas emissions. In-vehicle testing is performed with a 2014 Silverado on a closed course to understand the criteria to activate AFM. Parameters required for AFM activation are monitored by recording vehicle CAN bus traffic. Simulink models of the engine plant and SoftECU are developed to represent the operation of the engine system.
2017-03-28
Technical Paper
2017-01-1042
Eric J. Passow, Paras Sethi, Max Maschewske, Jason Bieneman, Kimm Karrip, Paul Truckel
Current market demands in conjunction with increased emission legislation's, have OEM’s striving to improve fuel economy and reduce CO2 emissions. One way to meet these demands, is through engine downsizing. Engine downsizing allows for reduced pumping and frictional losses. However, to maintain drivability, specifically in trucks and SUV's, power density increase through the addition of either a turbocharger or supercharger is necessary. Furthermore, engine efficiencies have been improved through reduced engine speed, paired with high gear count transmissions, providing an opportunity for manufactures to achieve desired drivability (strong acceleration coupled with fuel efficient high gears for cruising). With these advancements taken to improve engine/vehicle efficiency, gasoline turbo charge direct injected (GTDI) engines operate at low engine speeds with high torque output.
2017-03-28
Technical Paper
2017-01-1682
Matthew von der Lippe, Mark Waterbury, Walter J. Ortmann, Bernard Nefcy, Scott Thompson
The FMEA and DV&PV process of developing automotive products requires identifying and repeatedly testing critical vehicle attributes and their response to noise factors that may impair vehicle function. Ford Electrified Powertrain Engineering has developed a new process and an automated scripting tool to streamline in-vehicle robustness testing and produce more accurate and repeatable results. Similar noise factors identified during the FMEA process are grouped together, condensed, and scripts are developed to simulate these noise factors using calibration parameters and vehicle controls. The automated testing tool uses the ATI Vision API and a graphical scripting interface to consistently simulate driver inputs with greater precision than a human calibrator and enable more sophisticated controls, which would have previously required experimental software builds.
2017-03-28
Technical Paper
2017-01-1671
Johannes Bach, Marc Holzäpfel, Stefan Otten, Eric Sax
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
2017-01-1672
Siddartha Khastgir, Gunwant Dhadyalla, Stewart Birrell, Sean Redmond, Ross Addinall, Paul Jennings
The advent of Advanced Driver Assistance Systems (ADAS) and autonomous driving has offered a new challenge for functional verification and validation. The explosion of the test sample space for possible combinations of inputs needs to be handled in an intelligent manner to meet cost and time targets for the development of such systems. Various test methods like VEHiL (Vehicle Hardware-in-the-Loop), Vehicle-in-the-Loop and Co-ordinated automated driving have been developed for validation of ADAS and autonomous systems. Increasingly, driving simulators are being used for testing ADAS and autonomous systems as they offer a safer and a more reproducible environment for verifying such systems. While each of these test methods serves a specific purpose, they have a common challenge between them. All of these methods require the generation of test scenarios for which the systems are to be tested.
2017-03-28
Technical Paper
2017-01-0536
William Goodwin, Claudio Mancuso, Nicolas Brown
The development of automotive embedded software and calibrations presently involves an expensive development cycle in terms of both time and cost. A primary reason is the associated expense and time require to apply the various technologies needed for software testing and calibration development. Early in the design cycle software-in-the-loop (SIL) and Hardware-in-the-Loop (HIL) systems are typically employed. Later stages use costly engine and vehicle hardware as part of the software test and calibration development process. During this phase propulsions systems may initially utilize dynamometers and eventually migrate to vehicle level testing. All these technologies contribute to large budgets and design times required for embedded software and calibration development.
2017-03-28
Technical Paper
2017-01-0453
Zane Yang
Considered in this study by the use of finite element model is a unit of assembled stator and one-way clutch (OWC) whose inner chamber is maintained at a given temperature of 150 degree C while its exterior housing surfaces are exposed to the room temperature. Two key components of dissimilar metals are assembled, as usual, at the room temperature, through the conventional interface fitting, to form a secured joint by the means of internal friction forces so that torque loads are capable to be transmitted. Due to the dissimilar materials and resulting difference in their thermal expansion coefficients, an outer component of aluminum from this joint tends to expand more than the inner component of steel when the temperature rises. This work is indented to demonstrate that using a combined thermal and structural FEA can play a pivoting role in designing not only a robust product, but also a vital test procedure that can really captures how the product functions.
2017-03-28
Technical Paper
2017-01-0138
Chris Lim, Peter Ireland, Nicholas Collett
The analysis of thermal fields in the underhood region is complicated by the complex geometry and the influence of a multitude of different heat sources. This complexity means that running full CFD analyses to predict the thermal field in this region is both computationally expensive and time consuming. A method of predicting the thermal field using linear superposition has been developed in order to analyse the underhood region of a simplified Formula One racecar, though the technique is applicable to all vehicles. The use of linear superposition allows accurate predictions of the thermal field within a complex geometry for varying boundary conditions with negligible computational costs once the initial characterisation CFD has been run. A quarter scale, rear end model of a Formula One racecar with a simplified internal assembly is considered for analysis, though the technique can also be applied to commercial and industrial vehicles.
2017-03-28
Technical Paper
2017-01-1679
Felix Martin, Michael Deubzer
The increasing complexity of automotive real-time applications, and the challenges arising with the change to multi-core processors put higher demands on the tools which are involved in the development of such systems. With tracing it is possible to record the dynamic behavior of time-critical applications and use the data to monitor safety-critical requirements. However, not all trace techniques are sufficient for this use-case. Several factors like the available hardware, bandwidth, timing accuracy, and number of traceable objects must be considered. Additionally, traces are usually not recorded on a level that is suitable for timing analysis. Hence, a transformation of the trace may be necessary. In this paper we give an overview of existing trace techniques and discuss their applicability for the timing analysis of embedded systems. We also take limitations which may be caused by existing hardware platforms into consideration.
2017-03-28
Technical Paper
2017-01-0174
Ravi Rungta, Noori Pandit
A simple, fast, and inexpensive screening corrosion test has been developed that will supplement the currently utilized SWAAT test (ASTM G85) to evaluate relative corrosion performance of condensers from various suppliers and using differing material combinations and manufacturing processes including CAB brazed Silfluxed tube, zinc sprayed tube, and bare folded tube. The SWAAT test is utilized with no failure in 21 days as the “PASS” criterion. Most condensers tend to “pass” this test which makes it difficult to compare corrosion performance of the condensers supplied by various manufacturers. This paper will present the development of test parameters and the initial results. The test replicates the mode of attack observed in SWAAT as well as field returned units.
2017-03-28
Technical Paper
2017-01-0720
Omar Ramadan, Luc Menard, David Gardiner, Aaron Wilcox, Gary Webster
This paper is a continuation of work previously discussed in SAE 2014-01-0179 and SAE 2015-01-0805, which is targeted at the progress of further improving the capability, precision, and durability of the Ignition Quality Tester (IQT™) and associated ASTM D6890/EN15195 Test Methods. The results presented in those two papers indicated how the new generation of IQT™ with the TALM Precision Package (TALM-IQT™) upgrade can markedly improve the precision of the ASTM D6890 and CEN EN 15195 Derived Cetane Number (DCN) test methods. This paper will evaluate the performance of the upgraded instruments over the past 20 months of their participation in ASTM’s National Fuel Exchange Group (NEG) diesel fuel exchange program. It will also present a comparison of the published precision of all four ASTM Cetane Number (CN) and Derived Cetane Number (DCN) standard test methods that participated meaningfully in the ASTM NEG diesel fuel exchange program.
2017-03-28
Technical Paper
2017-01-0745
R. Vallinayagam, S. Vedharaj, Yanzhao An, Alaaeldin Dawood, Mohammad Izadi Najafabadi, Bart Somers, Bengt Johansson
This study demonstrated the change in combustion homogeneity from conventional diesel combustion via partially premixed combustion towards HCCI. Experiments are performed in an optical diesel engine at a speed of 1200 rpm with diesel fuel. Single injection strategy is employed and the fuel is injected at a pressure of 800 bar. The cylinder pressure at TDC is maintained at 35 bar and a high-speed video of the combustion process is captured through optical piston. The high speed video is processed to study the combustion homogeneity based on an algorithm reported in previous studies. Starting from late fuel injection timings, the combustion homogeneity is investigated by advancing to early fuel injection timings. For late fuel injection timings, a direct link between fuel injection timing and combustion phasing is noticed. At advanced fuel injection timings, the start of combustion is independent of fuel injection timing.
2017-03-28
Technical Paper
2017-01-1410
Richard F Lambourn, James Manning
It occasionally happens, following a collision between a car and a pedestrian or in a deliberate assault with a motor vehicle, that the pedestrian comes to be caught or wedged beneath the car, and that the driver then travels on for a considerable distance, afterwards claiming to have been unaware of the presence of the person. In such incidents, investigators are often incredulous that the driver should not have been able to “feel” that there was something underneath his car, and that he did not stop at least to find out what the problem was. The only practical way of investigating the matter further is to carry out practical tests with a suitable car and dummy. This paper describes the tests performed by the authors following one such incident, and begins with accounts of two previous incidents investigated in a more subjective fashion.
2017-03-28
Technical Paper
2017-01-1007
Piotr Bielaczyc, Andrzej Szczotka, Joseph Woodburn
Increasingly stringent legislation aims to reduce exhaust gas particulate levels - and not only for vehicle with Diesel engines. Various authorities have set limits for the mass of particulate (PM) emitted over a legislative driving cycle and the EU has added particle number (PN) limits. Additionally, there is considerable interest in particulate emissions from engine types traditionally assumed to have zero particulate emissions - port fuel injected vehicles running on gasoline, LPG and CNG. Regional specifics such as drive cycles mean that the legislative particulate emissions result varies from jurisdiction to jurisdiction, even where the same vehicle is used for testing.
2017-03-28
Technical Paper
2017-01-1002
Daisuke Tanaka, Ryo Uchida, Toru Noda, Andreas Kolbeck, Sebastian Henkel, Yannis Hardalupas, Alexander Taylor, Allen Aradi
Reducing engine-out particulates is one of the main issues of direct injection gasoline engines and further efforts are still needed to comply with near-future emission regulations. However, engine-out particulate emission characteristics strongly depend on fuel properties associated with the combustion design and/or calibration, due to the complicated mechanisms of particulate formation, including both physical and chemical processes. For these reasons, the purpose of this work was to gain a fundamental understanding of which fuel property parameters are responsible for particulate emission characteristics, associated with key intermediate behavior in the engine cylinder. Accordingly, engine tests were carried out using various fuels having different volatility and chemical compositions under different coolant temperature conditions. In addition, a fundamental spray and film visualization analysis was also conducted using a constant volume vessel.
2017-03-28
Technical Paper
2017-01-1035
Xingyu Xue, John Rutledge
Diesel engine downsizing aimed at reducing fuel consumption while meeting stringent exhaust emissions regulations is currently in high demand. The boost system architecture plays an essential role in providing adequate air flow rate for diesel fuel combustion while avoiding impaired transient response of the downsized engine. Electric Turbocharger Assist (ETA) technology integrates an electric motor/generator with the turbocharger to provide electrical power to assist compressor work or to electrically recover excess turbine power. Additionally, a Variable geometry turbine (VGT) is able to bring an extra degree of freedom for the boost system optimization. The electrically-assisted turbocharger, coupled with VGT, provides an illuminating opportunity to increase the diesel engine power density and enhance the downsized engine transient response. This paper assesses the potential benefits of the electrically-assisted turbocharger with VGT to enable heavy-duty diesel engine downsizing.
2017-03-28
Technical Paper
2017-01-1427
Daniel Koch, Gray Beauchamp, David Pentecost
Tire disablement events can cause a drag force that slows a vehicle’s speed. In this study, the magnitude of the deceleration was measured in 29 high speed tread separation and air loss tests. The tires tested were circumferentially cut to create partial and full tread separations, or prepared to lose air rapidly. The deceleration rates were corrected for the slope of the road, aerodynamic drag and rolling resistance of each vehicle tested. These deceleration rates can assist in reconstructing the speed of a vehicle involved in an accident following a tire disablement.
2017-03-28
Technical Paper
2017-01-1231
Chun Tang, Natee Limsuwan, Nurani Chandrasekhar, Zhichun Ma, Jacob Krizan, Joel Hetrick, Wei Wu
Abstract: Machine three phase current driven by PWM switching inverter in PM machine drive is not ideal sinusoidal, containing different levels of harmonics. The current harmonics have important impact on the electrical machine torque ripple which could translate into transmission and vehicle level noise vibration and harshness (NVH). In this work, the current waveforms were measured from dyno test at prescribed torque and speed levels, and the electric machine torque ripple was computed with the measured current. This paper will focus on the investigation of the current harmonics behaviors and features at various torque and speed conditions, the impact on torque ripple, and the possible mitigation method to reduce torque ripple.
2017-03-28
Technical Paper
2017-01-1237
Ahmad Arshan Khan, Michael J. Kress
For high performance motor controls applications such as electric vehicles, accurate motor parameter knowledge is required. Motor parameters like inductances, resistance and permanent magnet flux linkage are difficult to obtain and measure directly. These parameters vary considerably depending on operating conditions. Various methods are available in literature to obtain motor parameters offline. Usually motor designers use finite element analysis to calculate inductance estimate. Normally motor data necessary to come up with finite element model is unavailable and not provided by manufacturers. Even if provided, simulation results rarely match experimental results. Other methods commonly used in industry are locked rotor test and no-load test. However, parameters obtained by using such tests differ from parameters in real operating conditions.
2017-03-28
Technical Paper
2017-01-0331
Qiuren Chen, Haiding Guo, Katherine Avery, Xuming Su, HongTae Kang
Fatigue crack growth tests have been carried out to investigate the mixed mode fatigue crack propagation behavior of an automotive structural adhesive BM4601. The tests were conducted a compound CMM (Compact Mixed Mode) specimen under load control with 0.1 R ratio and 3Hz frequency. A long distance moving microscope was employed during testing to monitor and record the real time length of the fatigue crack in the adhesive layer. The strain energy release rates of the crack under different loading angles, crack lengths and loads were calculated by finite element method. The pure mode I and mode II tests show that an equal value of mode I strain energy release rate results in over ten times higher FCGR (Fatigue Crack Growth Rate) than the mode II stain energy release rate does. The mixed mode tests results show that under a certain loading angle, the mixed mode FCGR is changed by changing the load, which is contrary to the find in pure mode I and mode II tests.
2017-03-28
Technical Paper
2017-01-1683
Adit Joshi
Software for autonomous vehicles is highly complex and requires enormous amount of vehicle testing to achieve a certain level of confidence in safety, quality and reliability. According to the RAND Corporation, a 100 vehicle fleet running 24 hours a day 365 days a year at a speed of 40 km/hr, would require 17 billion driven kilometers of testing and take 518 years to fully validate the software with 85% confidence [1]. In order to reduce cost and time to accelerate autonomous software development, Hardware-in-the-Loop (HIL) simulation is used to supplement vehicle testing. For autonomous vehicles, path following and trajectory tracking controls are an integral part for achieving lateral control. Combining the aforementioned concepts, this paper focuses on a real-time implementation of a path-following lateral controller, developed by Freund and Mayr [2].
2017-03-28
Technical Paper
2017-01-0381
L. Karhik, R. Dinesh Kumar, E. Prasanna Kumar, V. Srinivasa Chandra
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
2017-01-0391
Daniel Meyer, Peter Maehling, Thomson Varghese, Jeffery Lewis
Precise and accurate internal-combustion engine pressure measurements are typically built upon extremely low level piezoelectric sensor signals acquired in the laboratory. In turn, these minute signals must be accurately conditioned using electronic charge amplifiers and then processed for meaningful analysis. Laboratory standard operating procedures often overlook the importance of timely and rigorous calibration of the equipment, or perform them without using sufficient environmental controls. In some facilities, years have been allowed to pass between metrology-quality calibrations, introducing the potential for significant out-of-tolerance conditions and non-compliance when compared to accredited measurement standards. Environmental, aging and operator factors influencing calibration metrology and in-use accuracy are presented in this paper, along with a method and example for estimating the calibration interval needed to specify calibration frequency for charge amplifiers.
2017-03-28
Technical Paper
2017-01-0384
Bo Zhang, Qingzhu Cai, Yong Lu, Jianfeng Wang, Lei Wang, Wenqian Chen, Lie Yao, Yuqing Gu, Tao Gu, Shawn S. You
Abstract ADAMS, SIMULINK, and ADAMS-SIMULINK co-simulation models of component test systems, Multi-Axis-Simulation-Table (MAST) systems, and spindle-coupled vehicle testing system (MTS 329) were created. In the ADAMS models, the mechanical parts, joints, and bushings were modeled. Hydraulic and control elements were absent. The SIMULINK models modeled control and hydraulic elements including actuator dynamics, servo valve dynamics, closed loop control, three-variable control, matrix control, and coordinate transformation. However, the specimen had to be simplified due to the limitation of SIMULINK software. The ADAMS-SIMULINK co-simulation models considered hydraulic and control components in the SIMULINK portion and mechanical components in ADAMS portion. The interaction between the ADAMS and SIMULINK portions was achieved using ADAMS/Control.
2017-03-28
Technical Paper
2017-01-0393
Keunsoo Kim
Abstract Fuel tank in vehicle must hold the fuel in a stable way under any driving condition. However, the fuel tank might not conserve the fuel firmly in case a crack emerged while the fuel tank is exposed to different driving condition. Basically, when the engine is in purging at a normal ambient temperature before fuel boiling, the pressure inside the fuel tank decreases. However, the pressure inside a fuel tank increases while a vehicle is driven at extreme hot ambient temperature as fuel is boiling. This repetitive pressure change in the fuel tank comes with fuel tank’s physical expansion and shrink, which would cause a damage to the fuel tank. The main purpose of this research is to investigate the root cause of why fuel tank cracks at a fatigue point. We also aim to set up the method of how to test durability of the fuel tank in association with the pressure inside the tank.
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