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Equivalent Radiated Power driven optimization for driveline housings using simulation tools to cut-down the project time

VE Commercial Vehicles, Ltd.-Suresh Kumar Kandreegula, Hemant Nishad, Dheeraj Singh, Kunal Kamal
  • Technical Paper
  • 2019-28-2533
To be published on 2019-11-21 by SAE International in United States
In the field of Automotive industry, being competitive makes you succeed. Industry is moving towards advancement day by day. New technologies to improve fuel efficiency, crash resistance, vehicle noise levels have been trending. At VECV, we have traditionally worked on CAE of driveline housings (clutch housing & transmission housing) based on static, dynamic and transient loadings. Currently, weight optimization technique depends on the structural and dynamic loading conditions, but do not consider acoustic concerns. Powertrain housings are highly prone to vibrations and leads to high level of noise. Noise has been constant issue in the casting components associated to driveline. There have been lot of research going on to reduce the level of noise and vibrations in the vehicle driveline, which ultimately leads to fuel efficiency and ergonomic benefits. Low noise generation can also lead to saving of lot of resources deployed to dampen the noises. In order to capture the acoustic responses of the system and to improve the design based on acoustic responses, a comprehensive analysis of newly developed driveline housings (clutch housing…
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Green’s Function Extraction from Atmospheric Acoustic Propagation

  • Magazine Article
  • TBMG-35363
Published 2019-10-01 by Tech Briefs Media Group in United States

Acoustic waves propagating in the atmosphere may undergo many effects including refraction by temperature and wind velocity gradients, scattering by atmospheric turbulence, absorption by the atmosphere (fluid), diffraction by terrain features, and absorption and reflection by a porous ground. As a result, there may be insonification in acoustic shadow zones, amplitude and phase fluctuations of the propagating sound signals, loss of signal coherence, changes in the interference maxima and minima of the direct ground reflected waves, and multipath effects. Understanding these effects is important for a variety of military applications, such as acoustic source localization and classification, noise propagation in the atmosphere, and the development of new remote sensing techniques of the atmosphere.

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Green's Function Extraction from Atmospheric Acoustic Propagation

Aerospace & Defense Technology: October 2019

  • Magazine Article
  • 19AERP10_08
Published 2019-10-01 by SAE International in United States

Understanding what affects acoustic waves propagating in the atmosphere is important for a variety of military applications including the development of new remote sensing techniques.

Acoustic waves propagating in the atmosphere may undergo many effects including refraction by temperature and wind velocity gradients, scattering by atmospheric turbulence, absorption by the atmosphere (fluid), diffraction by terrain features, and absorption and reflection by a porous ground. As a result, there may be insonification in acoustic shadow zones, amplitude and phase fluctuations of the propagating sound signals, loss of signal coherence, changes in the interference maxima and minima of the direct ground reflected waves, and multipath effects. Understanding these effects is important for a variety of military applications, such as acoustic source localization and classification, noise propagation in the atmosphere, and the development of new remote sensing techniques of the atmosphere.

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Optimizing NVH for EVs

Automotive Engineering: October 2019

Lindsay Brooke
  • Magazine Article
  • 19AUTP10_03
Published 2019-10-01 by SAE International in United States

Unique acoustic and harmonic challenges require an integrated approach to simulation and analysis. An expert at Adaptive Corp. explains.

Despite global sales market share stuck at single-digit levels, electric vehicles (EVs) are steadily filling the development pipelines at major OEMs. And as engineers are acutely aware, EVs bring a paradigm shift in the noise, vibration and harshness (NVH) arena. Their harmonic spectra are dramatically different than those of even the smoothest, most refined combustion-engine vehicles and hybrids.

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Compact, Lightweight, CMC-Based Acoustic Liner

  • Magazine Article
  • TBMG-35287
Published 2019-10-01 by Tech Briefs Media Group in United States

In the wake of recent developments that have reduced fan and jet noise contributions to overall jet-engine noise, aircraft designers are turning their attention toward reducing engine core noise. Innovators at NASA’s Glenn and Langley Research Centers are developing a compact, lightweight acoustic liner based on oxide/oxide ceramic matrix composite (CMC) materials.

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Imaging and Vibro-Acoustic Diagnostic Techniques Comparison for a GDI Fuel Injector

Istituto Motori CNR-Luigi Allocca, Daniela Siano, Alessandro Montanaro, Maria Antonietta Panza
  • Technical Paper
  • 2019-24-0058
Published 2019-09-09 by SAE International in United States
This work presents the results of an experimental investigation on a GDI injector, in order to analyze fuel injection process and atomization phenomenon, correlating imaging and vibro-acoustic diagnostic techniques.A single-hole, axially-disposed, 0.200 mm diameter GDI injector was used to spray commercial gasoline in a test chamber at room temperature and atmospheric backpressure. The explored injection pressures were ranged from 5.0 to 20.0 MPa. Cycle-resolved acquisitions of the spray evolution were acquired by a high-speed camera.Simultaneously, the vibro-acoustic response of the injector was evaluated. More in detail, noise data acquired by a microphone sensor were analyzed for characterizing the acoustic emission of the injection, while a spherical loudspeaker was used to excite the spray injection at a proper distance detecting possible fuel spray resonance phenomena. In order to monitor vibration throughout the injection event, the injector was also equipped with an accelerometer sensor, adhesively mounted on the holder. Tests in both dry and fuel injection conditions allowed to distinguish the pure mechanical operation of the injector related to the needle opening and closing, and the effects…
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Benefit of a Lightweight Frunk

Autoneum Management AG-Federico Di Marco, Flavio Pezzani, Andreas Daving, Luca Mazzarella
Published 2019-06-05 by SAE International in United States
Due to the increasing number of battery electric vehicles (BEVs), the engineering fields regarding driving comfort and NVH issues are becoming more and more challenging: many new factors affect the development of BEVs NVH package. The noise sources related to the powertrain are different from the traditional ones of internal combustion engines, for instance due to the presence of tonal components, strong harmonics and potential whining noise.To satisfy NVH specifications and the need for lightweight solutions to increase driving range, it is important to mask as much as possible the noise coming from the engine bay with materials both lightweight and acoustically performing. Moreover, for electric vehicles new interesting solutions are possible with the introduction of new components that do not find room under the hood of ICE or hybrid vehicles. These components, if properly designed, could lead to significant NVH benefits. The present paper reports the NVH effects of one of these new components, the frunk, a small compartment inside the engine bay, functionally similar to the trunk.In this paper, the design-by-simulation of a…
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Structural Vibration and Acoustic Analysis of a 3-Phase AC Induction Motor

Peyman Poozesh
Kettering University-Anand Krishnasarma, Allan Taylor, Javad Baqersad
Published 2019-06-05 by SAE International in United States
This paper aims to study the NVH and acoustic performance of a 3-phase AC induction motor in order to develop an approach to reduce the magnetic component of noise from an electric motor in an electric vehicle (EV). The final goal of this project is to reduce the magnetic component of sound from the motor by making modifications to the end bracket of the motor housing.EVs are being considered the future of mobility mainly due to the fact that they are environment-friendly. As many companies are already investing in this technology, electric drives are set to become extremely popular in the years to come. The heart of an EV is its motor. Modern electric vehicles are quiet, furthermore with the lack of an IC engine to mask most sounds from other components, the sound from the electric motor and other auxiliary parts become more prominent. The primary source of electromagnetic noise in a motor arises from magnetic flux variations in the air gap which interfere with the resonant frequencies of the stator core. These flux…
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Developing a Custom Data Acquisition Software Package for a Self-contained Acoustic Test Facility

Kolano and Saha Engineers, Inc.-Richard Kolano, Sagar Patil, Pranab Saha
Published 2019-06-05 by SAE International in United States
This paper provides an overview of a custom software developed to obtain measurement data in a self-contained acoustic test facility system used for conducting random incidence sound absorption tests and sound transmission loss tests on small samples in accordance with SAE J2883 and J1400 standards, respectively. Special features have been incorporated in the software for the user to identify anomalies due to extraneous noise intrusion and thereby to obtain good data. The paper discusses the thoughts behind developing user-friendly algorithms and graphical user interfaces (GUI) for the sound generation, control, data acquisition, signal processing, and identifying anomalies.
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Psychoacoustic Order Tonality Calculation

HEAD acoustics GmbH-Julian Becker, Roland Sottek
Published 2019-06-05 by SAE International in United States
Quantifying tonalities in technical sounds according to human perception is a task of growing importance. The psychoacoustic tonality method, published in the 15th edition of the ECMA-74 standard, is a new method that is capable of calculating the perceived tonality of a signal. Other methods, such as Prominence Ratio or Tone-to-Noise Ratio do not consider several essential psychoacoustic effects. The psychoacoustic tonality is based on a model of human hearing and thus is able to model human perception better than other methods. The algorithm described in ECMA-74 calculates tonality over time and frequency. In practice, tonalities often originate from rotating components, for example, parts of an electric motor. In these cases, quantification of the tonality of orders is often more interesting than the tonality over frequency. In this paper, an extension of the psychoacoustic tonality according to ECMA-74 is presented. With this extension, it is possible to calculate the order tonalities by using the rotational speed characteristics of the measured signal in order to control the parameters of the auditory filter bank. Two of the…
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