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2015-06-15
Technical Paper
2015-01-2142
Colin Hatch, Roger Gent, Richard Moser
Summary Initial results from a hybrid electro-thermal electro-mechanical simulation (HETEMS) analysis tool are presented and compared to data measured during a dedicated icing trial. Temperatures and ice shed prediction data are compared with the data measured on a full size wing tested in the CIRA Icing Wind Tunnel (IWT) Additional Test Section (ATS). Background The demand for low power ice protection systems was one of the components of the EU Clean Sky initiative [1]. Under Clean Sky a research programme HETEMS looked at the development of a tool to analyse electro-thermal (ET) and electro-mechanical (EM) ice protection systems (IPS). The tool was intended to analyse independent ET and EM systems or a hybrid system using both technologies combined. The aims and scope of the tool are presented in [2]. The HETEMS software was developed around open source tools for the aerodynamic analysis [3] and mechanical failure analysis [4] in conjunction with in-house software.
2015-06-15
Technical Paper
2015-01-2279
Giovanni Rinaldi, Chris Moon, Bret Engels
A unique Matlab-based coded engineering software tool (Time-Frequency Analyzer Core) was developed that allows users to process acquired time data to help in identifying sources and paths of noise and vibration (in the experience of the authors). The Time-Frequency Analyzer Core (TFAC) software does not replace commercial off the shelf software/hardware NV specific tools such as modal analysis, ODS, acoustic mapping, order tracking, etc., rather it aims at providing basic, yet powerful data inspection and comparison techniques in a single software tool that facilitate drawing conclusions and identifying most effective next steps. The features and advantages of using this software tool will be explained, along with a description of its application to a few different cases (automotive and off highway/agricultural).
2015-06-15
Technical Paper
2015-01-2278
Rohit Ravindran, Debajit Das, Sivaraman P, Gyan Arora
Torsional vibration is a common phenomenon occurring in power driven mechanical systems, like automobiles and commercial vehicles. It can have an adverse impact on powertrain related noise as well as the durability of transmission and drivetrain components. Hence minimizing torsional vibration levels associated with powertains has become important. In this context accurate measurement and representation of angular acceleration is of paramount importance. A methodology was developed for in house vehicle level torsional vibration measurement, analysis and representation of results. The evaluation of torsional vibration has two major aspects. First, the acquisition of raw rotational data and secondly, the processing of acquired data to arrive at usable information from which inferences and interpretations can be made about the behavior of the rotating element. This paper describes the development process followed for establishing a torsional vibration evaluation methodology.
2015-06-15
Technical Paper
2015-01-2281
Shrirang Deshpande, Randall Allemang
Spectral maps and order tracks are tools which are susceptible to improper sensor location on rotating machinery and to measurement noise. On a complex/large rotating system, the major behavior in a particular direction cannot be observed by using standard digital signal processing averaging techniques on different sensor outputs. Also, measurement noise cannot be reduced by applying averaging - due to the slew rate of the system. A newly developed technique tested on experimental data, is presented which uses singular value decomposition (SVD) as its basis to improve the observability of rotating systems. By using data acquired from multiple accelerometers on a machine, singular values – obtained from a SVD of the cross-power matrix at each 2-D point in the frequency-RPM domain – can be plotted in a color-map format similar to a RPM spectral map.
2015-06-15
Technical Paper
2015-01-2280
Bernd Philippen, Roland Sottek
Transfer Path Analysis and Synthesis is a widely-used troubleshooting and engineering method in the development process of a car. An engine TPA model should include the engine mounts because they are important elements of the structure-borne paths from the engine to the driver’s ears. This allows identifying if the structure, the sound radiation or the mount is a weak point of the transmission. A mount can be characterized, e. g., by a mount attenuation function, a four-pole model, or a simple parametric mount model. If the mount characteristics are known, the influence of a different mount on the structure-borne sound can be virtually predicted without a real modification. The mount characteristics could be determined on special test rigs but the transferability to the real situation is often questionable because the same boundary conditions on the test rig and in the car are difficult to guarantee.
2015-06-15
Technical Paper
2015-01-2282
Roland Sottek, Wade Bray
For many years in vehicle and other product noise assessments, tonality measurement procedures such as the Tone-to-Noise Ratio, Prominence Ratio and DIN 45681 Tonality have been available to quantify the audibility of prominent tones. Especially through the recent past as product sound pressure levels have become lower, disagreements between perceptions and measurements have increased across a wide range of product categories including automotive, Information Technology and residential products. One factor is that tonality perceptions are caused by spectrally-elevated noise bands of various widths and slopes as well as by pure tones, and usually escape measure in extant tools. Near-superpositions of discrete tones and elevated narrow noise bands are increasingly found in low-level technical sounds. Existing pure-tone methodologies tend to misrecognize an elevated noise band as general masking lowering the audibility of a tone in the measured vicinity, whereas perceptually they add.
2015-06-15
Technical Paper
2015-01-2284
Chris Hocking, Simon Antonov, Arsham Shahlari
The higher cylinder peak pressure and pressure rise rate of modern diesel and gasoline fueled engines tend to increase combustion noise while customers demand lower noise. The multiple degrees of freedom in engine control and calibration mean there is more scope to influence combustion noise but this must first be measured before it can be balanced with other attributes. An efficient means to realize this is to calculate combustion noise from the in-cylinder pressure measurements that are routinely acquired as part of the engine development process. This publication reviews the techniques required to ensure accurate and precise combustion noise measurements. First, the dynamic range must be maximized by using an analogue to digital converter with sufficient number of bits and selecting an appropriate range in the test equipment.
2015-04-14
Technical Paper
2015-01-1303
Wenli Li, Xiao-Hui Shi, Dong Guo, Peng Yi
An approach using dynamic emulation of mechanical loads for testing and validation of the vehicles' Transmission will be presented in the paper. In order to reduce costs and shorten new vehicle development cycle time, vehicle simulation on the driveline test bench is an attractive alternative at the development phase to reduce the quantity of proto vehicles. This test method moves the test site from the road to the bench without the need for real chassis parts. Dynamic emulation of mechanical loads is a Hardware-in-the-loop (HIL) procedure, which can be used as a supplement of the conventional simulations in testing of the operation of algorithms without the need for the prototypes. The combustion engine is replaced by a electric drive dynamometer, which replicates the torque and speed signature of an actual engine, The road load sistance of the vehicle on a real test road is accurately simulated on Load dynamometer by corrected road load forces.
2015-04-14
Technical Paper
2015-01-1018
Ryoko Sanui, Katsunori Hanamura
Surface pores that are open to the inlet channel below the surface play a particularly important role in the filtration of particulate matter (i.e., soot) inside the walls of a diesel particulate filter (DPF); they are closely related to the pressure drop and filtration efficiency through the DPF as well as the performance of the regeneration process. In this study, a scanning electron microscope (SEM) was used to dynamically visualize the soot deposition process at the particle scale as “time-lapse” images corresponding to the different increases in the pressure drop at each time step. The soot was first trapped at the deepest areas of the surface pores because the porous channels in this area were constricted by silicon carbide grains; soot dendrite structures were observed to grow and finally cause obstructions here.
2015-04-14
Technical Paper
2015-01-0613
Donghong Ning, James Coyte, Hai Huang, Haiping Du, Weihua Li
Abstract This paper presents a study on experimental vibration simulation using a multiple-DOF motion platform for heavy duty vehicle seat suspension test. The platform is designed to have 6-DOF with the advantages of high force-to-weight ratio, high dexterity and high position accuracy. It can simulate vehicle vibrations in the x, y and z translational axis and in the roll pitch and yaw axis rotation. To use this platform to emulate the real vibration measured from vehicle seat base under real operation for vehicle seat suspension test in lab, an Inertial Measurement Unit (IMU) is applied to collect the acceleration data from a real vehicle. An estimation algorithm is developed to estimate the displacement from the measured acceleration. The estimated displacement is then used to calculate the length of each leg of the platform so that the platform can generate the motion similar to the measured one.
2015-04-14
Technical Paper
2015-01-1092
Gabriela Achtenova, Ondrej Milacek
Abstract The purpose of the article is to describe different possibilities of the innovative concept of the closed-loop test rig. The performed tests will be demonstrated with the example of measured data. Firstly the article will describe in detail the design of the test stand and both torque units. The power flow in the closed-loop circuit will be described and measured to find out the power losses of all parts. The measurement will be done for manual and planetary pretensioning mechanism. The comparison of the overall efficiency and demanded power for both torque units will be given. For evaluation of gearbox efficiency, the magnitude of power losses will be evaluated for different revolutions, torque levels and shifted speeds. For a long term tests, the unmanned operation is prepared. For this purpose is the stand equipped with electromechanical shift robots. The description of its concept and functioning will be part of the paper.
2015-04-14
Technical Paper
2015-01-1487
Andreas Teibinger, Harald Marbler-Gores, Harald Schluder, Veit Conrad, Hermann Steffan, Josef Schmidauer
Structural component testing is essential for the development process to have an early knowledge of the real world behaviour of critical structural components in crash load cases. This is due to the earlier availability and lower cost of hardware components in comparison to the whole vehicle. Current approaches mainly use originally moving deformable barriers and therefore a full vehicle test facility is needed. The objective of this work is to show the development for a self-sufficient structural component test bench, which can be used for different side impact crash load cases. The test bench is designed with simulations and includes a control for the force impact. This test bench is able to reproduce the same intrusion speeds as in whole vehicle tests and doesn’t block a full vehicle test facility.
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
2015-01-1672
Clemens Biet, Roland Baar
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 addition to that, with the shown concept all of the regular turbocharger test bench measurement points stay untouched as well.
2015-04-14
Journal Article
2015-01-1697
Daniel Freudenhammer, Brian Peterson, Carl-Philipp Ding, Benjamin Boehm, Sven Grundmann
Within automotive research and design, efforts are often focused on the engine geometry design for optimization of performance and efficiency. Within spark-ignition (SI) engines, the intake and cylinder geometry play an important role in defining the in-cylinder flow, which is regarded as a key parameter influencing charge-filling, mixture preparation, and combustion [1]. An efficient optimization of the intake- and in-cylinder geometry requires knowledge of the three-dimensional flow in the entire volumetric domain. Previous measurements however, have been limited to point-wise or planar velocimetry measurements. Magnetic resonance velocimetry (MRV) is an advanced diagnostic tool to investigate average 3D flow topology within the entire measurement domain in a fast and cost-efficient way. Since optical access is not needed for data acquisition, the use of MRV is convenient in highly complex geometries for which traditional velocimetry techniques are often limited.
2015-04-14
Journal Article
2015-01-0647
Rafael Fietzek, Stephan Rinderknecht
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 to realistically reproduce the loads, which act on the powertrain, the steering and the suspension during a test drive.
2015-04-14
Technical Paper
2015-01-0802
Claudio Marcio Santana, Jose Eduardo Mautone Barros, Matheus Guilherme França Carvalho, Helder Alves de Almeida, Jr.
A burning process in a combustion chamber of an internal combustion engine is very important to know the maximum temperature of the gas, the combustion speed and time delay ignition of fuel air mixture. The automotive industry has invested considerable amounts of resources in simulations and numerical modeling in order to obtain relevant information about the processes in the combustion chamber and then extract the maximum engine performance, control emissions and in formulating new fuels. This work aimed at general construction and instrumentation of a shock tube for measuring the fuel ignition delay time. Specific objectives determined the reaction raté and delay time of ignition Diesel S25, ethanol with 5 % additive enhancer cetane number, B100 biodiesel and Diesel reference. The results were correlatéd with the number of cetane fuels and compared with the times of known delays ignition of Diesel and biodiesel.
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.
2015-01-14
Technical Paper
2015-26-0064
Asmita Manwatkar, Prasad S Phale, Moqtik Ashok Bawase, Mangesh Ramesh Saraf
Abstract Used oil analysis plays an important role in the field of engine development, considering that it can give brief idea about performance of lubricant/ oil being used, its compatibility with the system under considerations. At present, regular testing is done like elemental analysis using Inductive Coupled Plasma (ICP) which can give idea about wear elements and additive elements. But it does not give information on morphological characterization of particles. In present work, Environmental Scanning Electron Microscopy technique with EDAX detector is used for characterizing the used oil. Oil is filtered on suitable paper and the particles collected on paper are analyzed. This gives the information on morphology and size of particles, their elemental analysis and mapping so that the sources can be judged. Size of wear metal particle is very important factor as even few bigger size particles are more detrimental than large number of smaller particles.
2015-01-14
Technical Paper
2015-26-0224
Ramsai Ramachandran, Nilesh Kumar Dehariya, Gaurav Kumar, Himanshu Agarwal, Sukhchain Singh
Abstract BIW (Body-in White) is a type of vehicle structure formed by spot welding of different sheet metal components. The BIW structure should be designed to support the maximum load potential under various performance conditions. Thus the structure should have good strength as well as stiffness. Torsion Stiffness of BIW is the amount of torque required to cause a unit degree of twist. It is often considered as a benchmark of its structural competence due to its effect on various parameters like ride, handling, lateral load distribution and NVH performance of vehicle. The paper aims to design and develop a test methodology and test fixtures for measuring the BIW torsion stiffness with repeatability of test results and also have an (R2>0.99) for the measured values in the test.
2014-10-13
Journal Article
2014-01-2637
Katsufumi Kondo, Junya Takahashi, Tetsuya Aizawa
Abstract Wall-deposition of soot particles occurs due to the interaction between spray flame and cylinder liner wall/piston surface, which can potentially affect soot morphology after the in-flame formation/oxidation processes and before the exit from engine cylinder. In order to investigate these effects, flame wall impingement was simulated in a constant volume combustion vessel and thermophoretic soot sampling was conducted for Transmission Electron Microscopic analysis. A TEM grid for the sampling was exposed to a single-shot diesel spray flame multiple times and the variation of soot morphology (concentration, primary particle diameter and aggregate gyration radius) among the multiple exposures was compared. Furthermore, a newly designed impingement-type sampler vertically exposed the grid to the spray flame and sampled soot particles under different boundary condition from that of conventionally used skim-type sampler.
2014-10-13
Journal Article
2014-01-2582
José Galindo, José Ramón Serrano, Pedro Piqueras, Javier Gómez
Abstract Calibration of internal combustion engines at different altitudes, above or below sea level, is important to improve engine performance and to reduce fuel consumption and emissions in these conditions. In this work, a flow test rig that reproduces altitude pressure variation is presented. The system stands out by its altitude range, compactness, portability and easy control. It is based on the use of turbomachinery to provide the target pressure to the engine intake and exhaust lines. The core of the system is composed of a variable geometry turbine (VGT) with a waste-gate (WG) and a mechanical compressor. Given a set of turbomachinery systems, the operation pressure and the air mass flow are controlled by the speed of the mechanical compressor and the VGT and WG position. A simple modification in the installation setup makes possible to change the operating mode from vacuum to overpressure.
2014-09-28
Journal Article
2014-01-2523
Nils Perzborn, Carlos Agudelo, Georg Peter Ostermeyer
Abstract Inertia dynamometers are commonly used to determine the friction coefficient of brake assemblies. Dynamometers are a well-established platform, allow testing under controlled conditions, exhibit a good correlation to many situations encountered in real driving, and are comparatively economical and less time-consuming than full vehicle test. On the other side of the spectrum is the use of scaled tribometer. These test systems make possible a test without the entire brake corner. This separation allows the investigation of the frictional-contact only (frictional boundary layer) speedily and independently of a given brake system or vehicle configuration. As the two test systems (inertia dynamometers and tribometers) may have different users with possibly different tasks, the question remains regarding how comparable the two systems are. These issues provide incentives to better define the fields of investigations, correlation, and applicability for the two systems.
2014-09-16
Technical Paper
2014-01-2182
Evan Racine, Zachary Lammers, Street Barnett, John Murphy, Quinn Leland
Abstract The purpose of this study is to set up a laboratory test apparatus to analyze aircraft flight control EMAS' electrical and thermal energy flow under transient and dynamic flight profiles. A hydraulic load frame was used to exert load to the EMA. The actuator was placed within an environmental chamber which simulates ambient temperature as function of altitude. The simulated movement or stroke was carried out by the EMA. The under test EMA's dynamic load, stroke, and ambient temperature were synchronized through a real time Labview DAQ system. Motor drive voltage, current, regenerative current, and motor drive and motor winding temperature were recorded for energy analysis. The EMA under test was subjected to both transient and holding load laid out in a test matrix.
2014-04-01
Technical Paper
2014-01-0830
Shulian Zhang, Weiping Wang
Abstract This paper reports the extraordinary properties and industry applications of Nd: YAG Microchip Laser Feedback Interferometer, Nd: YAG LFI. The Michelson interferometer has been invented for more than a century and is widely used in science and industry today. The Nd: YAG LFI, which is based on laser feedback effect instead of ordinary interferometry, has the different structure from Michelson interferometer, and then extraordinary properties. Therefore the Nd: YAG LFI can be used as a traditional laser interferometer with nano-meter resolution and a few meters measurement range. At the same time Nd: YAG LFI can also measure the displacement of light, thin, black, transparent (water, alcohol, glass surface) objects, even liquid evaporation rate.
2014-04-01
Technical Paper
2014-01-0831
Ping Zhong, Kang Zhang, Xu Chen, Yunlong Shi, Lianxiang Yang
Abstract The assembling accuracy of two contactors during the relay switch production is an important factor affecting the quality of relay. An embedded machine vision quality Inspection system has been developed for electric relay production line inspection. The proposed system can provide online feedback on the quality of the relays by measuring the distance of the gap between the contacts of them. Two CMOS imaging sensors are operated for image acquisition and the parallel working mode is realized under dual-channel mode. A red light illumination system has been adopted to eliminate the imaging noise from the reflection of the surfaces of copper sheet. Before the test, the features areas in the image of same type relay is selected as template and saved in the computer.
2014-04-01
Technical Paper
2014-01-0827
Songgang Li, Guobiao Yand, Weiming Zeng
Abstract The port structure consisting of spur pile, vertical pile and beam is subjected to impact loads, so its internal stress state of each point will rapidly change over time. Dynamic photoelastic method is used to study the dynamic stress and stress wave propagation. With epoxy resin and other materials, a photoelastic model of beam to column connection structure is processed and product. The dynamic response of the model under the impact load by the free fall is researched by the dynamic photoelastic method, and recorded by the new digital dynamic photoelastic system with a laser source and high-speed photography system. The internal dynamic stress propagation and distribution, the maximum shear stress and the dynamic stress concentration problems can be obtained by analyzing the dynamic response.
2014-04-01
Technical Paper
2014-01-0826
Hang Yin, Weiming Zeng, Guobiao Yang, Songgang Li
Abstract When an object was subjected an impact loading, stress wave was produced in the object. Studying the regularity of stress-wave propagation was significant to the study of objects subjected to impact loading. When stress wave travelled in the object, principal stress on free boundary was useful to theoretical analysis and calculation. In this article, a new kind of dynamic photoelastic apparatus was used. Isochromatic and isoclinic of the object subjected to impact loading could be obtained combining dynamic photoelastic experiment and related test equipment. By analyzing the isoclinic, there would be a conclusion that the angle between the isoclinic and the free boundary was not 0°or 90°. So the values of the two principal stress on the boundary were all not 0. The result obtained from the electrometric method came to the same conclusion. Analysis showed the result of dynamic photoelastic method was compatible with the result of electrometric method.
2014-04-01
Technical Paper
2014-01-0829
Guobiao Yang, Jingyu Wang, Qirong Zhu, Ruhua Fang, Lianxiang Yang
Abstract With the rapid development of computing technology, high-speed photography system and image processing recently, in order to meet growing dynamic mechanical engineering problems demand, a brief description of advances in recent research which solved some key problems of dynamic photo-elastic method will be given, including:(1) New digital dynamic photo-elastic instrument was developed. Multi-spark discharge light source was replaced by laser light source which was a high intensity light source continuous and real-time. Multiple cameras shooting system was replaced by high-speed photography system. The whole system device was controlled by software. The image optimization collection was realized and a strong guarantee was provided for digital image processing. (2)The static and dynamic photo-elastic materials were explored. The new formula and process of the dynamic photo-elastic model materials will be introduced. The silicon rubber mold was used without the release agent.
2014-04-01
Technical Paper
2014-01-0177
Ying Wang, Fei Han, Yue Kong, Weiwen Deng
Abstract Vision-based Advanced Driver Assistance Systems (Vi-ADAS) has achieved rapid growth in recent years. Since vehicle field testing under various driving scenarios can be costly, tedious, unrepeatable, and often dangerous, simulation has thus become an effective means that reduces or partially replaces the conventional field testing in the early development stage. This paper proposes a quantitative assessment framework for model quality evaluation of 3D scene under simulation platform. An imaging model is first built. The problem of solving the imaging model is then transformed into the problem of intrinsic image decomposition. Based on Retinex theory and Non-local texture analyses, a superior intrinsic image decomposition method is adopted to evaluate the fidelity of the 3D scene model through the degree of deviation to the Reflectance and Shading intrinsic maps respectively.
Viewing 1 to 30 of 1278

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