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Noise and Vibration Optimization Using TMR Analysis for CI Engine Fueled by Blends of Simarouba Methyl Ester

SVPM COLLEGE OF ENGINEERING-Sangram Dashrath Jadhav
  • Technical Paper
  • 2019-01-1894
To be published on 2019-09-16 by SAE International in United States
Today’s frenetic engine manufacturing and transportation sector and its related traces viz; noise and vibration of our modern societies has adverse effect on environment as well as all of us. Generally, vehicle extensively tested to withstand against mechanical shocks, noise, vibration etc. While, accordingly make the provision such as suspension, dampers, air bags etc. still the problem of noise/vibration day-by-day incrementally arise and become severe with the age of vehicles. Noise/vibration is a controllable pollutant that deserves the attention were all the scientific community work hard for controlling their harmful effects. Modern research affords us the opportunity to understand the subject better and to develop advance technologies. Widely immediate slogan and goal of all industries might be to reduce Noise/vibration on predominantly basis while, make the quietest and smoothest running Engines. Noise/vibration cause and adverse effect on C.I engine, engine component and ultimately vehicle, may reduce the life of the engine. To, reduce the dependency on diesel fuel (Due to rapid worldwide depletion) Biodiesel is one of the immediate, alternative and complimentary solution. In the…
 

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
To be published on 2019-08-15 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. Contemporarily, 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 distinct the pure mechanical operation of the injector related to the needle opening and closing, and…
 
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Role of Dynamic Stiffness in Effective Isolation

Deere & Company-Yuzhen Yang
John Deere India Pvt, Ltd.-Balavardhan Reddy Dasabai
Published 2019-06-05 by SAE International in United States
In any machinery, avoiding noise and vibration completely is a difficult task due to the structural dynamic behaviors of components. To safeguard the operator, it is important to best isolate the operator station from NVH environment. Cabin isolation is an important aspect to minimize structure borne noise and tactile vibrations to be transferred into the cabin. Isolators are selected based on the isolation system inertial properties at mounting locations in the operating frequency range interested. The most important assumption to select isolators are that the active side and passive side of the isolators are nearly rigid so impedance mismatch is created for effective isolation.This paper describes the importance of dynamic stiffness of the structures on both the active and passive side for better NVH performance. NVH performance of passive side is evaluated analytically and computationally in terms of tactile vibrations and structure borne noise for various ratios of the dynamic stiffness over isolator stiffness. The isolator selection criterion is also discussed based on rigid body modes, operating frequency range, transmissibility ratio, and kinematic energy distributions.
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Model Verification of CAE with NVH-Test Acting on Downsized Car Engines

NVH-testing Powertrain-Janos Ribarits
Volvo Cars, Engine Vibrations CAE-Urban Rönnqvist
Published 2019-06-05 by SAE International in United States
Today’s trend of combustion engine development for cars is characterized with; high torque, low engine speed, low weight, high degree of cyclic irregularity, low excitation frequency due to fewer cylinders active e.g. 4-cylinder or less.This implies in respect of vibrations that it is crucial to control powertrain rigid body modes and place these were they cannot be reached and induced by the low exciting harmonic frequencies for low engine speeds or idling. It is also important to control the overall flexible vibration modes.A mathematical CAE model is created in simulation software AVL-EXCITE in order to handle the vibration phenomenon as a first step. But it is absolutely necessary to “verify” these models with real measurements in respect of NVH and if needed upgrade the CAE model if there are detected deviations. The NVH-test is done with testing tool DEWESoft.The purpose of below paper is to do model verification on a concrete example in respect of powertrain vibrations. Volvo Cars in-line 4-cylinder VEA diesel engine in rig installation is the object for the paper of model…
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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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Noise and Vibration End-of-Line Production Testing and Analysis Challenges

Bruel & Kjaer North America, Inc.-Chris Moon
Published 2019-06-05 by SAE International in United States
Theoretical modeling continues to play a larger role in noise and vibration engineering; however, until products are perfectly made, there will be a need to evaluate their end of the production line performance. Manufacturing production of a wide range of items has classically involved some amount of subjective and/or evolved objective quality testing along, or at the end of the production line. This testing can have goals of determining product safety, durability, functionality, and/or the vibration/sound quality. A vibration-based measurement approach is frequently used for many of those goals. Often, many modern products utilize some combination of electric motors, internal combustion engines, and power transmission rotational components. The end-of-line testing for many of these rotational components is after many years now heavily refined in the measurement and analysis methods, and the separation of good, bad and marginally bad samples may not always be challenging. It is frequently the non-standard types of products or unique operating conditions, either as subcomponents or assemblies, which may provide unique challenges to the typical measurement and analysis methods. Additionally, depending…
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Numerical Prediction and Verification of Noise Radiation Characteristics of Diesel Engine Block

Deere & Company-Sanghoon Suh
John Deere Technology Center India-Devendra Mandke, Deepak Ghaisas, Sachin Pawar
Published 2019-06-05 by SAE International in United States
To assess the contribution of structure-borne noise from an engine, it is critical to characterize the dynamic and vibro-acoustic properties of the engine components and assembly. In this paper, a component level study of a three-cylinder diesel engine block is presented. Virtual analysis was done to predict the natural frequencies and mode shapes of an engine block in the first step. Then, these results were used to decide the optimum test locations and an experimental modal test was conducted on the engine block. The initial virtual model results for the natural frequencies and mode shapes were correlated with the results from test. Then, the virtual model was updated with the damping derived from experimental modal test to match the vibration frequency response functions. Further, the virtual model was used for prediction of vibro-acoustic transfer functions. The vibro-acoustic transfer functions were also obtained from test. The results of transfer function were correlated with the test. In future, we plan to use this approach for prediction of the vibration and vibro-acoustic transfer functions for sub-assembly and eventually…
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A Non-Contact Technique for Vibration Measurement of Automotive Structures

Kettering University-Vanshaj Srivastava, Javad Baqersad
Published 2019-06-05 by SAE International in United States
The automotive and aerospace industries are increasingly using the light-weight material to improve the vehicle performance. However, using light-weight material can increase the airborne and structure-borne noise. A special attention needs to be paid in designing the structures and measuring their dynamics. Conventionally, the structure is excited using an impulse hammer or a mechanical shaker and the response is measured using uniaxial or multi-axial accelerometers to obtain the dynamics of the structure. However, using contact-based transducers can mass load the structure and provide data at a few discrete points. Hence, obtaining the true dynamics of the structure conventionally can be challenging. In the past few years, stereo-photogrammetry and three-dimensional digital image correlation have received special attention in collecting operating data for structural analysis. These non-contact optical techniques provide a wealth of distributed data over the entire structure. However, the stereo camera system is limited by its field of view of the cameras and can only measure the response on the parts of the structure that cameras have the line of sight. Therefore, a single pair…
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Target Development for Transmission and Electric Motor NVH

FEV North America, Inc.-Todd Tousignant, Alex Ford, Kiran Govindswamy
Ford Motor Company-Justin Dech, Frederick Vanhaaften, Matthew Hettenhouse
Published 2019-06-05 by SAE International in United States
It is a common practice to conduct NVH fingerprinting and benchmarking assessments at the powertrain level, to understand source level noise and vibration. To assess the NVH influence of engine, e-motor, and transmission, sub-system testing is often conducted in addition to full powertrain testing. These powertrain or sub-system investigations provide valuable information regarding the status of “source” level excitations relative to targets and / or competitive powertrains. In the case of transmissions and e-machines, it is particularly important to understand source level tonal content and how this will be perceived at the vehicle level. However, variation in component design results in differences in order content, which complicates the process of objectively comparing multiple products.Multiple methods are presented here for characterizing tonal content of transmission and e-machines, based on assessments conducted in a component hemi-anechoic dynamometer test cell. Ultimately, sound quality is assessed by the customer at the vehicle level. Accordingly, the methods developed incorporate means of cascading results between component level and vehicle level. Furthermore, since the perception of tonal noise content is dependent upon…
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Structural Vibration of an Elastically Supported Plate due to Excitation of a Turbulent Boundary Layer

University of Michigan-Jonmarcos Diaz, Kevin Maki, Nickolas Vlahopoulos
Published 2019-06-05 by SAE International in United States
High-Reynolds number turbulent boundary layers are an important source for inducing structural vibration. Small geometric features of a structure can generate significant turbulence that result in structural vibration. In this work we develop a new method to couple a high-fidelity fluid solver with a dynamic hybrid analytical-numerical formulation for the structure. The fluid solver uses the Large-Eddy Simulation closure for the unresolved turbulence. Specifically, a local and dynamic one-equation eddy viscosity model is employed. The fluid pressure fluctuation on the structure is mapped to the dynamic structural model. The plate where the flow excitation is applied is considered as part of a larger structure. A hybrid approach based on the Component Mode Synthesis (CMS) is used for developing the new hybrid formulation. The dynamic behavior of the plate which is excited by the flow is modeled using finite elements. However, the rest of the surrounding structure is modeled using finite elements for the static modes and an analytical solution for the dynamic modes of the CMS decomposition. The two main elements of the new work,…
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