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2017-09-04
Technical Paper
2017-24-0042
Ali Jannoun, Xavier Tauzia, Pascal Chesse, Alain Maiboom
Residual gas plays a crucial role in the combustion process of spark ignited engines. It acts as a diluent and has a huge impact on pollutant emissions (NOx and CO emissions), engine efficiency and tendency to knock. Therefore, characterizing the residual gas fraction is an essential task for engine modelling and calibration purposes. Thus, an in-cylinder sampling technique was developed on a spark ignited VVT engine to measure residual gas fraction during the compression phase. Two gas sampling valves were flush mounted to the combustion chamber walls; they are located between the intake valves and between intake and exhaust valves respectively. Sampled gas was stocked in a sampling bag using a vacuum pump and measured with a standard gas analyzer. This paper describes in details the sampling technique and proposes a methodology allowing the evaluation of the residual gas fraction. For this purpose, five kinds of tests were undertaken.
2017-09-04
Technical Paper
2017-24-0129
Vladimir Merzlikin, Svetlana Parshina, Victoria Garnova, Andrey Bystrov, Alexander Makarov, Sergey Khudyakov
The core of this paper is reduction of exhaust emission and increase of diesel efficiency due to application of microstructure ceramic semitransparent heat-insulating coatings (SHIC). The authors conducted experimental study of thermal state of internal-combustion engine piston head with a heat-insulating layer formed by plasma coating method. The paper presents physical and mathematical simulation of improved optical (transmittance, reflectance, absorption, scattering) and thermo radiative (emittance) characteristics determining optimal temperature profiles inside SHIC. The paper considers the effect of subsurface volumetric heating up and analyzes temperature maximum position inside subsurface of this coating. Decrease of SHIC surface temperature of the coated piston in comparison with temperature of traditional opaque heat-insulating coatings causes NOx emission reduction.
2017-09-04
Technical Paper
2017-24-0138
Giovanni Meccariello, Livia Della Ragione
In the context of a transport sustainability, some solutions could be proposed from the integration of many disciplines, architects, environmentalists, policy makers, and consequently it may be addressed with different approaches. These solutions would be apply at different geographical levels, i.e. national, regional or urban scale. Moreover, the assessment of cars emissions in real use plays a fundamental role for their reductions. This is also the direction of the new harmonized test procedures (WLTP). Furthermore, it is fundamental to keep in mind that the new WLTC cycle will reproduce a situation closer to the reality respect to the EUDC/NEDC driving cycle. In this paper, we will be focused on vehicle kinematic evaluation aimed at valuation of traffic situation and emissions.
2017-09-04
Technical Paper
2017-24-0140
Roberto Aliandro Varella, Gonçalo Duarte, Patricia Baptista, Pablo Mendoza Villafuerte, Luis Sousa
Due to the need to properly quantify vehicle emissions in real world operation, Real Driving Emissions (RDE) test procedures will be used for measuring gaseous emissions on new EURO 6 vehicles.at the RDE 1 & 2: Commission Regulation (EU) 2016/427 of 10 March 2016 amending Regulation (EC) No 692/2008 as regards emissions from light passenger and commercial vehicles. Updated regulations have been enhanced to define RDE tests boundaries and data analysis procedures, in order to provide an accurate way to obtain representative results. The boundary conditions defined for vehicle testing include external atmospheric temperature, which can range from 0ºC to around 30ºC, for moderate conditions and -7oC up to 35oC for extended conditions in RDE tests. As a result of this range of possible test ambient temperature, pollutant emissions and energy consumption can vary considerably.
2017-06-05
Technical Paper
2017-01-1851
Taewook Yoo, Ronald W. Gerdes, Seungkyu Lee, Daniel Stanley, Thomas Herdtle, Georg Eichhorn
Abstract Several methods for evaluating damping material performance are commonly used, such as Oberst beam test, power injection method and the long bar test. Among these test methods, the Oberst beam test method has been widely used in the automotive industry and elsewhere as a standard method, allowing for slight bar dimension differences. However, questions have arisen as to whether Oberst test results reflect real applications. Therefore, the long bar test method has been introduced and used in the aerospace industry for some time. In addition to the larger size bar in the long bar test, there are a few differences between Oberst (cantilever) and long bar test (center-driven) methods. In this paper, the differences between Oberst and long bar test methods were explored both experimentally and numerically using finite element analysis plus an analytical method. Furthermore, guidelines for a long bar test method are provided.
2017-06-05
Technical Paper
2017-01-1863
Bhaskar Avutapalli, Mayuresh Pathak, Shalini Solipuram, Ken Buczek, Aaron Lock
Abstract Road noise and speech intelligibility are becoming ever more important, irrespective of the vehicle size, due to vehicle refinement as well as connectivity with mobile communication equipment. With better aerodynamic designs, development of refined powertrains, and a tectonic shift from I.C. engine to electric motors, road noise and wind noise will become more apparent to the customer and hence will become a priority for automakers to refine their vehicles. This paper describes the efforts undertaken to identify the road noise paths and develop countermeasures for a compact SUV vehicle. A hybrid test/CAE approach was followed to improve road noise performance of this vehicle. This effort involved developing tire CAE models from physical hardware and creating synthesized road-load input from data taken on roads.
2017-06-05
Technical Paper
2017-01-1881
Charles Moritz, Satyajeet Deshpande
Abstract As part of the update process to SAE J1637, Laboratory Measurement of the Composite Vibration Damping Properties of Materials on a Supporting Steel Bar, the Acoustical Materials Committee commissioned a round robin study to determine the current laboratory-to-laboratory variation, and to better understand best practices for composite loss factor measurements. Guidance within the current standard from a previous round robin study indicates a coefficient of variation of 35% for laboratory-to-laboratory measurements. It was hoped that current instrumentation and test practices would yield lower variability. Over the course of 2 years, 8 laboratories tested 4 bars, three damped steel bars and one bare steel bar. These bars were tested at -20°C, -5°C, 10°C, 25°C, 40°C, and 55°C. The damping materials were intentionally selected to provide low damping, moderate damping, and high damping as difficulties in determining the composite loss increase with increased damping.
2017-06-05
Technical Paper
2017-01-1886
Siwen Zhang, Jian Pang, Jun Zhang, Zhuangzhuang Ma, Xiaoxuan Zhang, Congguang Liu, Lihui Deng
Abstract A subjective evaluation method for the air-borne sound insulation of vehicle body in reverberation room is developed and the correlation between the subjective preference and objective noise reduction level (NRL) is investigated in this paper. The stationary vehicle's interior noise is recorded by using a digital artificial head under a given white noise excitation in the reverberation room, which demonstrates more credible than those in traditional road test methods. The recorded noises of six different vehicles are replayed and evaluated subjectively by 22 appraisers in a sound quality room. The paired comparison scoring method is employed and the check and statistic methods for the subjective scores are introduced. The subjective preference is introduced and calculated by the statistics and normalization of the effective scores, which can indicate an overall preference ranking of all the six vehicles numerically.
2017-06-05
Technical Paper
2017-01-1908
Rong Guo, Jun Gao, Xiao-kang Wei, Zhao-ming Wu, Shao-kang Zhang
Abstract The statement of the engine shake problem is presented through comparing the quarter vehicle models with the rigid-connected and flexible-connected powertrain which is supported on the body by a rubber mount. Then the model is extended by replacing the rubber mount as a hydraulic engine mount (HEM) with regard to the inertia and resistance of the fluid within the inertia track. Based on these, a full vehicle model with 14 degree of freedoms (DOFs) is proposed to calculate the engine shake, which consists of 6 of the powertrain, 1 of the fluid within the inertia track of the HEM, 3 of the car body and 4 of the unsprung mass. Simulation analysis based on the proposed model is implemented, through which the conclusion is drawn that the HEM has great influence on the body and seat track response subjected to front wheel inputs, compared with the rubber mount.
2017-06-05
Journal Article
2017-01-1774
Fabio Luis Marques dos Santos, Tristan Enault, Jan Deleener, Tom Van Houcke
Abstract The increasing pressure on fuel economy has brought car manufacturers to implement solutions that improve vehicle efficiency, such as downsized engines, cylinder deactivation and advanced torque lock-up strategies. However, these solutions have a major drawback in terms of noise and vibration comfort. Downsized engines and lock-up strategies lead to the use of the engine at lower RPMs, and the reduced number of cylinders generates higher torque irregularities. Since the torque generated by the engine is transferred through flexible elements (clutch, torsional damper, gearbox, transmission, tire), these also impact the energy that is transferred to the vehicle body and perceived by the driver. This phenomenon leads to low frequency behavior, for instance booming noise and vibration. This paper presents a combined test and CAE modelling approach (1D/3D) to reverse engineer a vehicle equipped with a CPVA (centrifugal pendulum vibration absorber).
2017-06-05
Technical Paper
2017-01-1803
John Van Baren
Abstract The accumulated damage that a product experiences in the field due to the variety of vibration stresses placed upon it will eventually cause failures in the product. The failure modes resulting from these dynamic stresses can be replicated in the laboratory and correlated to end use environment to validate target reliability requirements. This presentation addresses three fundamental questions about developing accelerated random vibration stress tests.
2017-06-05
Technical Paper
2017-01-1800
Robert White
Abstract Several analytical tools exist for estimating a driveshaft’s critical speed, from simple elementary beam theory to sophisticated FEA models. Ultimately, nothing is better than a test, because no one will argue with the outcome from a well-designed measurement. Impact response measurements are easy, but they tend to over predict the critical speed. A test which sweeps the shaft speed up until failure is telling, but the speed causing failure is strongly dependent on even small amounts of variation in rotor unbalance. Waterfall plots of shaft displacement measurements offer the best indication of critical speed, however sometimes the resonance isn’t unmistakable or multiple resonances exist, making the critical speed unclear. A method less susceptible to system variation is offered here, fitting shaft orbit measurements to the theoretical single degree of freedom equation.
2017-04-11
Journal Article
2017-01-9177
N. Obuli Karthikeyan, R. Dinesh Kumar, V. Srinivasa Chandra, Vela Murali
Abstract In the modern automotive sector, durability and reliability are the most common terms. Customers are expecting a highly reliable product but at low cost. Any product that fails within its useful life leads to customer dissatisfaction and affects the reputation of the OEM. To eradicate this, all automotive components undergo stringent validation protocol, either in proving ground or in lab. This paper details on developing an accelerated lab test methodology for steering gearbox bracket using fatigue damage and reliability correlation by simulating field failure. Initially, potential failure causes for steering gearbox bracket were analyzed. Road load data was then acquired at proving ground and customer site to evaluate the cumulative fatigue damage on the steering gearbox bracket. To simulate the field failure, lab test facility was developed, reproducing similar boundary conditions as in vehicle.
2017-03-28
Technical Paper
2017-01-0138
Chris Lim, Peter Ireland, Nicholas Collett
Abstract 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 race car, 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 race car 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
2017-01-0174
Ravi Rungta, Noori Pandit
Abstract A simple and rapid immersion type corrosion test has been successfully developed that discriminates corrosion performance in condensers from various suppliers and with differing manufacturing processes. The goal is to develop a test specification that will be included in the Ford corrosion specification for condensers so that condensers received from various suppliers may be evaluated rapidly for their relative corrosion performance to each other. Sections from condensers from Supplier A (tube is silfluxed), Supplier B (tube is zinc arc sprayed), and Supplier C (bare folded tube with no zinc for corrosion protection) were tested in 2% v/v hydrochloric acid for 16, 24 and 48 hours. The results showed that in terms of corrosion performance, zinc arc sprayed Supplier B condenser performed the worst while Supplier C condenser performed the best with Supplier A in between.
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.
2017-03-28
Technical Paper
2017-01-0392
Dae-Un Sung, James Busfield, Yong Hyun Ryu
The vehicle elastomeric components such as engine mounts could be aged and degraded by environmental loads such as thermal and mechanical loads during long term usage by customers. These make the degradation of vehicle driving performance comparing with a new condition. In this study, the main cause of NVH (Noise, Vibration and Harshness) degradation of a used vehicle was analyzed. It could be identified by the analysis of vibration insulating property changes of elastomeric components. The properties changes of aged engine mounts were analyzed and compared with initial properties. The accelerated laboratory ageing test mode was developed for simulating the degradation of engine mounts by thermal load analysis. Moreover, parametric studies were carried out to identify the robust engineering design technique. The engineering design parameters of elastomers such as volume, thickness and mechanical loading types were identified to improve the degradation phenomenon.
2017-03-28
Journal Article
2017-01-0400
Theo Rickert
Abstract Hole drilling is a very common technique for measuring residual stresses. Adding an orbiting motion of the drill was found to improve hole quality in difficult to drill materials and has been in practice for decades. This study compares measurements using various orbiting amounts. Each measurement was repeated twice to evaluate measurement statistics. There is a distinct, though relatively small, effect of the hole shape when no orbiting is used. It disappears already when the hole is 50% larger than the tool size. Different orbiting amounts also produce systematically different results. These may be related to the absolute hole size.
2017-03-28
Technical Paper
2017-01-0381
L. Karthik, R. Dinesh Kumar, E. Prasanna Kumar, V. Srinivasa Chandra
Abstract This abstract work describes a method of data acquisition and validation procedure followed for a metal bumper used in commercial vehicle application. Covariance is considered as major phenomenon for repeatable measurements in proving ground data acquisition and it is to be maintained less than 0.05. In this project covariance of data acquisition is analyzed before physical simulation of acquired data. In addition to that, multiple testing conditions like uni-axial and bi-axial testing were carried out to attain the failure. PG data is used for bi-axial vibration test and conventional constant spectrum signal (CSD signal) is used for uni-axial vibration test. Target duration for uni-axial test (Z direction) was arrived using pseudo damage calculation. Strain gauges were installed in failure locations to compare PG data and rig data as well as to calculate strain life. Failures were simulated in bi-axial vibration test.
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
2017-01-0371
Raju Gandikota, Amit Nair, Kurt Miller
Abstract 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 by Feng (1) requires testing under uniaxial and biaxial stretching modes. The classic inflation of a circular disk for biaxial stretch mode poses stability and safety challenges. The test can also be sensitive to end constraints resulting in failure of materials at the constraints. Biaxial stretching with a hemispherical punch is explored in this work. The biaxial stretching allows controlled and repeatable testing. It establishes a 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 have been established. The method greatly simplifies testing and provides reliable data for a failure criterion for elastomers in numerical modeling.
2017-03-28
Technical Paper
2017-01-0341
Seyyedvahid Mortazavian, Javid Moraveji, Reda Adimi, Xingfu Chen
Abstract In this study, a finite element analysis method is developed for simulating a camshaft cap punching bench test. Stiffness results of simulated camshaft cap component are correlated with test data and used to validate the model accuracy in terms of material and boundary conditions. Next, the method is used for verification of cap design and durability performance improvement. In order to improve the computational efficiency of the finite element analysis, the punch is replaced by equivalent trigonometric distributed loads. The sensitivity of the finite element predicted strains for different trigonometric pressure distribution functions is also investigated and compared to strain gage measured values. A number of equivalent stress criteria are also used for fatigue safety factor calculations.
2017-03-28
Technical Paper
2017-01-0331
Qiuren Chen, Haiding Guo, Katherine Avery, Xuming Su, HongTae Kang
Abstract 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 on 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 using 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
2017-01-0004
Norbert Wiechowski, Thomas Rambow, Rainer Busch, Alexander Kugler, Norman Hansen, Stefan Kowalewski
Abstract Modern vehicles become increasingly software intensive. Software development therefore is critical to the success of the manufacturer to develop state of the art technology. Standards like ISO 26262 recommend requirement-based verification and test cases that are derived from requirements analysis. Agile development uses continuous integration tests which rely on test automation and evaluation. All these drove the development of a new model-based software verification environment. Various aspects had to be taken into account: the test case specification needs to be easily comprehensible and flexible in order to allow testing of different functional variants. The test environment should support different use cases like open-loop or closed-loop testing and has to provide corresponding evaluation methods for continuously changing as well as for discrete signals.
2017-03-28
Journal Article
2017-01-0014
Takashi Nomura, Kazuma Kawai
Abstract The EMI, electromagnetic interference, is tested for automobiles and components by the method defined in the international standard, CISPR 25. Regarding the automobile test, the EMI from the component installed in the automobile is measured by the antenna of an automobile. On the other hand on the component test, the EMI from the component is measured by a mono-pole antenna set forward of the component. However, components sometimes fail the automobile test even if its passed the component test due to the difference of the method. In this case, the component has to be designed again to pass the automobile test. Therefore, the prediction method of the automobile test result is required. In this paper, we tried to modify the standard component test configuration to predict the automobile test result for a fuel pump system in AM frequency band.
2017-03-28
Technical Paper
2017-01-1672
Siddartha Khastgir, Gunwant Dhadyalla, Stewart Birrell, Sean Redmond, Ross Addinall, Paul Jennings
Abstract The advent of Advanced Driver Assistance Systems (ADAS) and automated 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. This paper addresses this research gap by using constrained randomization techniques for the creation of the required test scenarios and test cases. Furthermore, this paper proposes an automated constrained randomized test scenario generation framework for testing of ADAS and automated systems in a driving simulator setup. The constrained randomization approach is deployed at two levels: 1) test scenario randomization 2) test case randomization.
2017-03-28
Technical Paper
2017-01-1671
Johannes Bach, Marc Holzäpfel, Stefan Otten, Eric Sax
Abstract Enhanced technological capabilities render the application of various, increasingly complex, functional concepts for automated driving possible. In the process, the significance of automotive software for a satisfactory driving experience is growing. To benefit from these new opportunities, thorough assessment in early development stages is highly important. It enables manufacturers to focus resources on the most promising concepts. For early assessment, a common approach is to set up vehicles with additional prototyping hardware and perform real world testing. While this approach is essential to assess the look-and-feel of newly developed concepts, its drawbacks are reduced reproducibility and high expenses to achieve a sufficient and balanced sample. To overcome these drawbacks, new flexible, realistic and preferably automated virtual test methods to complement real world verification and validation are especially required during early development phases.
2017-03-28
Technical Paper
2017-01-1683
Adit Joshi
Software for autonomous vehicles is highly complex and requires vast 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 95% confidence such that its failure rate would be 20% better than the current human driver fatality rate [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 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
2017-01-1682
Matthew von der Lippe, Mark Waterbury, Walter J. Ortmann, Bernard Nefcy, Scott Thompson
Abstract 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 has developed a new 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 API of a calibration software tool 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
2017-01-1679
Felix Martin, Michael Deubzer
Abstract In the automotive industry a steady increase in the number of functions driven by innovative features leads to more complex embedded systems. In the future even more functions will be implemented in the software, especially in the areas of automatic driving assistance functions, connected cars, autonomous driving, and mobility services. To satisfy the increasing performance requirements, multi- and many-core controllers are used, even in the classic automotive domains. This case study has been conducted in the steering system domain, but the results can be applied to other areas as well. Safety critical functions of classic automotive domains must fulfill strict real-time requirements to avoid malfunctions, which can potentially endanger people and the environment. For this reason, ISO 26262 requires verification of the performance and timing behavior of system critical functions.
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