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Viewing 121 to 150 of 8630
Article
2014-04-16
dSPACE offers a flexible solution for hardware-in-the-loop testing of electric motors, combining Scalexio architecture with a programmable FPGA board and scalable electronic load.
Article
2014-04-16
The latest release of the MapleSim toolbox from Maplesoft expands control design capabilities and supports parameterized controllers for improved flexibility.
Article
2014-04-16
The all-new sports car poses a crucial question: Is it too clever by half? Dr. Andre Ebner, who heads the company’s development of onboard systems, argues very strongly that it is not.
Article
2014-04-15
With its i3 slated to reach U.S. customer hands in early May, BMW is ramping up production of its first mass-produced all-electric vehicle.
Article
2014-04-14
Customers want quieter cabins, but industry trends are working against the engineers who strive to reduce noise, vibration, and harshness.
Article
2014-04-14
Backed by the world’s fifth-fastest computer, Argonne’s new VERIFI service combines unique test facilities along with focused expertise to help engine developers.
Article
2014-04-09
Misfire detection is most difficult, SAE Congress panel tells attendees, and overall emissions diagnosis is harder than with passenger cars and light-duty trucks.
Article
2014-04-07
Atego Vantage is an integrated solution combining model-based systems and software engineering with asset-based modular design.
Article
2014-04-07
Elysium’s CADfeature 11.3 is a feature-based program for repairing, migrating, and reporting on product engineering data in manufacturing.
Article
2014-04-07
Meggitt Sensing Systems introduces a line of Endevco general purpose isotron IEPE accelerometers designed to meet the needs of various test applications.
Article
2014-04-07
Multiquip recently chose Exa to evaluate and reduce noise propagation from its containerized power generators.
Article
2014-04-07
The Maulflex conduit system from TE Connectivity is a lightweight, flexible, customizable shielded electrical conduit system for rugged environments.
Article
2014-04-07
XCal-View software from Renishaw offers improved functionality and flexibility for laser calibration data analysis.
Article
2014-04-04
According to CD-adapco's Frederick Ross, the first, and most difficult, stage in the construction of a virtual prototype is the process of pulling together all of the individual CAD parts that define a vehicle.
Article
2014-04-01
Palmer Wahl Instrumentation Group’s Wahl DST500-FM temperature indicator with fixed probes is a high-accuracy, wide-range thermometer designed for hazardous locations where accurate and reliable temperature monitoring is critical.
Article
2014-04-01
Dakota Instruments’ 6A03 acrylic flow meters are offered with interchangeable direct reading scales for air, water, argon, oxygen, carbon dioxide, nitrogen, helium, and hydrogen.
Technical Paper
2014-04-01
Xiaoxun Chen, Yu Zhang, Yunqing Zhang, Ming Jiang
Abstract In the present study, the research of the exhaust system is performed in three steps. In the first step, the average driving degree of freedom displacement (ADDOFD) is calculated by the free modal analysis of the exhaust system. It is easy to find the reasonable location of the hanger according to the value of the ADDOFD, since it represents the relative size of some DOF's response displacement at excitation state. The second of which is to analyse the vibration isolation performance of the exhaust system based on the first step. The dynamic analysis of the exhaust system together with the powertrain is studied, by which way the unit sinusoidal excitation is applied at the powertrain's mass centre, so that the response force at the hanger can be obtained. Finally, the relationship between the constrained model of the exhaust system and the stiffness of the hanger is investigated, which is significant in engineering.
Technical Paper
2014-04-01
Zamir Zulkefli, Maurice Adams
Abstract Gears are used in numerous applications where mechanical power needs to be transmitted as in the powertrain of cars, buses and other vehicles. These gears can potentially be a significant source of high-frequency vibration and radiated noise in a vehicle, which can be both harmful and objectionable to any listeners in the vicinity. A proposed approach to addressing the gear mesh-frequency vibrations is to utilize the low pass filtering effect of a hydrostatic bearing in a gear mesh-frequency noise mitigation system. This paper describes an experimental investigation of the low pass filtering effect of a hydrostatic bearing using an experimental setup involving a widely available materials testing machine. By using the materials testing machine, appropriately sized hydrostatic bearing and externally pressurized fluid supply system, empirical data was collected that allowed the frequency response of the hydrostatic bearing to be determined. The frequency response of the hydrostatic bearing clearly shows a low pass filtering effect on the applied dynamic loads.
Technical Paper
2014-04-01
Miguel De la Cruz, Stephanos Theodossiades
Abstract In this paper, a direct correlation between transmission gear rattle experiments and numerical models is presented, particularly focusing on the noise levels (dB) measured from a single gear pair test rig. The rig is placed in a semi-anechoic chamber environment to aid the noise measurements and instrumented with laser vibrometers, accelerometers and free field microphones. The input torsional velocity is provided by an electric motor, which is controlled by a signal generator, aiming to introduce an alternating component onto the otherwise nominal speed; thus, emulating the engine orders found in an internal combustion engine. These harmonic irregularities are conceived to be the triggering factor for gear rattle to occur. Hence, the rig is capable of running under rattling and non-rattling conditions. The numerical model used accounts for the gear pair's torsional dynamics, lubricated impacts between meshing teeth and bearing friction. The results show that rattle is indeed triggered by the governing engine orders present in the transmission's primary input shaft.
Technical Paper
2014-04-01
Daniela Siano, Luigi Teodosio, Vincenzo De Bellis, Fabio Bozza
Abstract The present paper reports 1D and 3D CFD analyses of the air-filter box of a turbocharged VVA engine, aiming to predict and improve the gas-dynamic noise emissions through a partial re-design of the device. First of all, the gas-dynamic noise at the intake mouth is measured during a dedicated experimental campaign. The developed 1D and 3D models are then validated at full load operation, based on experimental data. In particular, 1D model provides a preliminary evaluation of the radiated noise and simultaneously gives reliable boundary conditions for the unsteady 3D CFD simulations. The latter indeed allow to better take into account the geometrical details of the air-filter and guarantee a more accurate gas-dynamic noise prediction. 3D CFD analyses put in evidence that sound emission mainly occur within a frequency range of 350 to 450 Hz. Starting from the above result, the original air-box design is modified through the installation of a single Helmholtz resonator, taking into account layout constraints and the influence on engine performance, as well.
Technical Paper
2014-04-01
Mehdi Safaei, Shahram Azadi, Arash Keshavarz, Meghdad Zahedi
Abstract The main end of this research is the optimization of engine sub-frame parameters in a passenger car to reduce the transmitted vibration to vehicle cabin through DOE method. First, the full vehicle model of passenger car including all its sub-systems such as engine, suspension and steering system is modeled in ADAMS/CAR and its accuracy is validated by exerting swept sine and step input. After that, the schematic geometry of sub-frame is modeled in CAD software and transferred to ADAMS/CAR. Hence, the efficiency of the sub-frame in terms of reducing the induced vibration to vehicle cabin is examined through the various road inputs e.g. swept sine, step and random road input type (B). The results will illustrate that the sub-frame has significant effect in reduction of transmitted vibration to occupants. In order to optimize the sub-frame parameters, the sensitivity analysis is performed to derive effective parameters of sub-frame using DOE method. In this regard, the parameters which have dominant effect on transmitted vibration (the stiffness of sub-frame bushing in vertical direction) are optimized via RSM (Response Surface Method) method.
Technical Paper
2014-04-01
Sandeep Mahadev Jadhav
Abstract Objective of this research is to reduce gear rattle and whine noise. Study includes measurement of noise, vibration on transmission for source identification in order to eliminate rattle, whine through optimization of gear design and clutch damper performance. In order to optimize, we measured transmission torsional vibration and analyzed for proper selection of clutch dampers to reduce engine vibration transfer function to transmission. Through Noise & Vibration FFT, order and color map analysis we identified noise sources and further scope for specific gears design improvement. Hence test methodology adopted for development of gears and clutch damper successfully eliminated noise.
Technical Paper
2014-04-01
S. Christopher Zugo, Craig D. Smith, Charles W. Braun, Joseph Kazour
Abstract The audible noise characteristics of direct injectors are important to OEM customers when selecting a high pressure gasoline fuel injector. The activation noise is an undesirable aspect that needs to be minimized through injector design, injector mounting, and acoustic treatments. Experimentally identifying the location and frequency of noise sources is beneficial to the improvement of injector designs. Acoustic holography is a useful tool in locating these noise sources by measuring a sound pressure field with multiple microphones and using this field to estimate the source location. For injector testing, the local boundary conditions of the noise source will affect the resultant sound field. Therefore, how the injector is mounted within the test fixture will change the resultant noise field measured. In this study, the process of qualifying an acoustic holography fixture using measurement system analysis for GDi fuel injector testing will be documented. The noise levels and source locations for different injector mounting conditions will be evaluated.
Technical Paper
2014-04-01
Chien- Hsing Li, Yong-Yuan Ku, Ko Wei Lin
Abstract Due to the energy safety and environment protection, increase the percentage of biodiesel blend has become one of world wide strategies. In the past research, using biodiesel would affect the engine performance and increase the exhaust emission. Fortunately, these problems can be solved through the rapidly development of engine control technologies and lightweight structure design. However, the consideration of light/downsizing engine design with the same power has brought out much combustion noise. According to the higher and higher proportion has been widely used over the world. There was less researches focus on the different blending biodiesel impact on combustion noise. The combustion noise correspond to different blending biodiesel (D100,B5,B8,B20,B40,B100) which made form waste cooking oil has been discussion in this study. The experimental by using engine which meet EURO-4 was designed to caught spectrum of the combustion noise via transient window which under the constant engine speed of 1500rpm, 2000rpm, 2500rpm, with different torque at 30%, 50% and 70% of each speed, respectively.
Technical Paper
2014-04-01
Shuming Chen, Dengzhi Peng, Dengfeng Wang
Abstract Automobile cabin acoustical comfort is one of the main features that may attract customers to purchase a new car. The acoustic cavity mode of the car has an effect on the acoustical comfort. To identify the factors affecting computing accuracy of the acoustic mode, three different element type and six different element size acoustic finite element models of an automobile passenger compartment are developed and experimentally assessed. The three different element type models are meshed in three different ways, tetrahedral elements, hexahedral elements and node coupling tetrahedral and hexahedral elements (tetra-hexahedral elements). The six different element size models are meshed with hexahedral element varies from 50mm to 75mm. Modal analysis test of the passenger car is conducted using loudspeaker excitation to identify the compartment cavity modes. All the acoustic cavity models are coupled with the structure model respectively, the cavity modes are calculated with structural-acoustic coupling model.
Technical Paper
2014-04-01
Hiroyuki Tanaka, Hisashi Ihara, Akira Satomura, Yasuhiko Wada, Hideto Momii, Tatsuya Suma
Abstract In order to enhance product attraction, it is important to reduce the impact noise when a vehicle go over bumps such as bridge joints. Vehicle performance to transitional noise phenomena is not yet analyzed well. In this paper, a prediction method is established by vector composition and inverse Fourier transform with the combination of Multibody Dynamics (MBD) and FEM. Also, a root cause analysis method is established with the following three mechanism analysis methods; transfer path analysis, mode contribution analysis, and panel contribution analysis.
Technical Paper
2014-04-01
Adarsh Venkata Padmanabhan, Hariram Ravichandran, Lokendra Pavan Kumar Pappala, Rangaraj Ramanan Durai
Abstract This paper will discuss information extraction from sound signals obtained using acoustic sensors which are strategically placed on the automotive body. The sound signal obtained contains useful information such as vehicle and road surface characteristics. The aforementioned information was spread out at different frequencies in the spectral distribution of the signal. Well defined filters for the corresponding frequency bands were used to isolate these characteristics and patterns pertaining to the identified useful information from the signal. The obtained information can be used as inputs for systems such as vehicle safety systems, power train systems and NVH (Noise, Vibration and Harshness) systems.
Technical Paper
2014-04-01
V. Jadon, G. Agawane, A. Baghel, Venkatesham Balide, R. Banerjee, A. Getta, H. Viswanathan, A. Awasthi
Abstract With significant decrease in the background noise in present day automobiles, liquid slosh noise from an automotive fuel tank is considered as a major irritant during acceleration and deceleration. All major international OEMs and their suppliers try to reduce sloshing noise by various design modifications in the fuel tank. However, most major activities reported in open literature are primarily based on performing various CAE and experimental studies in isolation. However, noise generation and its propagation is a multiphysics phenomenon, where fluid mechanics due to liquid sloshing affects structural behaviour of the fuel tank and its mountings which in turn affects noise generation and propagation. In the present study a multiphysics approach to noise generation has been used to predict liquid sloshing noise from a rectangular tank. Computational Fluid dynamics (CFD), Finite Element Analysis (FEA) and Boundary Element Method (BEM) simulation studies have been performed in a semi-coupled manner to predict noise.
Technical Paper
2014-04-01
Li Yan, Weikang Jiang, Jiangqi Zhou
Abstract Sound quality of vehicle interior noise affects passenger comfort. In order to improve the sound quality of a micro commercial vehicle, the vehicle interior noise under different conditions such as idle, constant speeds and accelerating is recorded by using artificial head with dual microphones. The sound quality of recorded noise is evaluated in both objective and subjective ways. Physical parameters of interior noise are calculated objectively, and annoyance score is analyzed subjectively using paired-comparison method. According to the regression analyzing of the annoyance score and the physical parameters, an objective evaluation parameter of the sound quality is employed. To analyze the vehicle body panel contribution to interior noise sound quality, the location and spectrum characteristics of major panel emission noise sources are identified based on partial singular valued decomposition (PSVD) method. By investigating the contribution of each noise sources to the sound quality evaluation formula, the dominant interior noise source is determined.
Technical Paper
2014-04-01
Jong Ho Lee
Abstract Since vehicle NVH reduction technology has improved dramatically, buzz, squeak and rattle (hereafter referred to as “BSR”) noise quantification from interior and exterior of the vehicle becomes an important factor to measure the quality of the vehicle. (The cost rate of BSR noise claims take around 10-15%, moreover BSR noise negatively affects customers to purchase vehicles.) Therefore, a research of BSR evaluation comes to the fore to make a premium car. In this paper, we would like to introduce the development of a vehicle excitation test mode, the full-vehicle BSR test system, and a sound acoustic camera to detect BSR noise. The test profiles were correlated with various road severities such as the domestic field test sites including 5,000km cross-country off road, 19 test tracks for BSR in R&D test center, and quality test tracks in domestic factories. These test modes were classified into 4 levels (Low-Normal-High-Crazy) by judging degrees of GRMS values. The full-vehicle test system can reproduce various field road profiles of the BSR for chassis parts, interior, and exterior for temperatures of −40∼60°C.
Viewing 121 to 150 of 8630

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