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In the last decade, the equivalent circuit model has been utilized to model lithium-ion batteries for electric vehicle applications. Different researchers have proposed a variety of equivalent circuit models from simple to complex ones. The parameters required to describe and build these equivalent circuit models are being extracted from the Hybrid Pulse Power Characterization (HPPC) Test data. This paper describes the process of the extraction of the equivalent circuit model parameters to build the battery models using different test methodologies such as HPPC and its modified versions. It also presents a case study with validated test results for a commercial light weight EV. Firstly, showing how the cell is characterized and then how the pack level cooling is developed to reach the required range based on an aggressive drive cycle.

In recent years, customers who are looking to buy or lease a car have placed more interest in exploring electrified vehicles including Battery Electric Vehicles (BEV), Hybrid Electric Vehicles (HEV), Plug-in Hybrid Electric Vehicles (PHEV) and Fuel Cell Electric Vehicles (FCEV) as new options in the automotive market. As the recent trends suggest, this interest is likely to be solidified, and people will start buying EVs more and more. These market trends show that the internal combustion engine (ICE) drivetrain soon will be progressively replaced by the electric drive unit for passenger car applications. The electric vehicles provide positive impacts such as instant torque delivery, overall vehicle comfort, noise and vibration. They also provide local environmental benefits by reducing greenhouse gas emissions. However, there are some major complexities for EVs to overcome before completely replacing ICE vehicles.

With the mass movement toward electrification and renewable technologies, the scope of innovation of electrification has gone beyond the automotive industry into areas such as electric motorcycle applications. This paper provides a discussion of the methodology and complexities of converting an internal combustion motorcycle to an electric motorcycle. In developing this methodology, performance goals including, speed limits, range, weight, charge times, as well as riding styles will be examined and discussed. Based on the goals of this paper, parts capable of reaching the performance targets are selected accordingly. Documentation of the build process will be presented along with the constraints, pitfalls, and difficulties associated with the process of the project. The step-by-step process that is developed can be used as a guideline for future build and should be used as necessary.

The main purpose of this paper is to develop a reliable bench test to understand the vibratory behavior of the half shafts under applied torque comparable to an idle condition. In some cases, the half shaft path is a major factor influencing the idle vibration in the vehicle. At idle condition vehicle vibrations are caused by engine excitation and then they pass through different paths to the body structure. Half shaft manufacturers generally characterize shaft joints for their frictional behavior and typically there is no data for vibration characteristics of the half shaft under idle conditions. However, for predictive risk management, the vibratory behavior of the half shaft needs to be identified. This can be achieved from measured frequency response functions under preloaded test conditions.

The objective of this paper is to develop a robust methodology to study internal combustion (IC) engine block vibrations and to quantify the contribution of combustion pressure loads and inertial loads (mechanical loads) in overall vibration levels. An established technique for noise separation that, until recently, has not been applied to engine noise is Wiener filtering. In this paper, the harmonic part of the overall vibration response of the IC engine block is removed, resulting in a residual broadband response which is uncorrelated to the source signal. This residue of the response signal and the similarly calculated residue of the combustion pressure represent the dynamic portion of their respective raw signals for that specific operating condition (engine speed and load). The dynamic portion of the combustion pressure is assumed to be correlated only to the combustion event.

The intent of this paper is to document comprehensive test-based approach to analyze the door-closing event and associated sound using structural and acoustic loads developed during the event. This study looks into the door-closing phenomenon from the structural interaction point of view between the door and the body of the vehicle. The study primarily focuses on distributing the door and body interaction as discrete multiple structural and acoustic phenomena. It also emphasizes on the structural and acoustic loads developed by the discretized interactions at the interfaces between the door and the body frame. These interfaces were treated to be the load paths from the door to the body. The equivalent structural and acoustic loads were calculated indirectly using the well-known Transfer Path Analysis (TPA) methodology for structural loads and the Acoustic Source Quantification (ASQ) methodology for acoustic loads.

In this paper, it is explained how composite structures, made of continuous fibers embedded in a polymer matrix, are designed and analyzed in the aerospace industry. The strategy is based on the building block approach, in which the knowledge on the composite material and structure is built step by step from the coupon level up to the final full scale structure. Damage is then discussed, as it can't be ignored when composites are concerned. The approach available in the SAMCEF finite element code is then described. It is based on the continuum mechanics approach, and allows studying the progressive failure of composites in the plies and at their interface (so considering delamination). The material models are described, and their use is illustrated at the coupon level. The identification procedure for this damage models is also discussed.

ACOUSTOMIZE™ is a new method of acoustic evaluation used for the purpose of understanding and optimizing NVH performance of vehicles. The following paper documents a case study of the ACOUSTOMIZE™ test methodology on a passenger car BIW. This study includes an analysis of noise flow through BIW locations, a comparison of noise sound levels through BIW cavities with and without a sound treatment package and a comparison of the original cavity sealing design package consisting of baffles, tapes and baggies to low density polyurethane NVH Foam. The results of the study show detection of complex BIW pass throughs that the body leakage test (BLT) was not able to find. In addition, the data shows improved noise reduction with the low density polyurethane foam versus the original cavity sealing design package.

The goal of this study is to measure the Noise, Vibration and Harshness (NVH) performance of passenger vehicle cavities under different drive conditions. Until now, little attention has been given to the impact of NVH performance of cavity fillers with respect to the driver's perception. To further understand this phenomenon, a four door sedan was instrumented with several microphones placed within different vehicle cavities. After instrumentation, the vehicle was tested under various road conditions; cruise, idle, street run, rough road and wide open throttle. The resulting data shows that there is a substantial noise presence in the hinge pillar and lower rocker cavities for all test conditions. The data also provides a means to rank the importance of the sound contribution of each vehicle cavities with respect to other cavities. To understand the NVH contribution of individual cavities to the driver's perception, the vehicle was placed inside a semi-anechoic chamber.

A new test methodology has been developed to quantify the performance of vehicle cavity fillers. This test methodology focuses on the vehicle Body in White (BIW) and provides a proper test environment for individual cavity fillers. Since the focus of the methodology is BIW, the proper boundary condition is automatically implemented and the results obtained from this test methodology can be utilized for an actual comparison of noise reduction (NR) performance for different cavity fillers. In this study a noise source generator was placed at different locations within the vehicle body to generate the desired noise level. The goal was to realistically simulate wind, tire and the powertrain noise sources at the vehicle level and evaluate the performance of the cavity fillers. By placing several microphones in the vicinity of the A, B, C and D pillars, the noise reduction performances of the individual cavity fillers were obtained.

This paper describes a comprehensive hybrid technique developed for optimization of damping materials on vehicle bodies. This technique uses finite element analysis (FEA) along with experimental techniques to complement each other. In this particular application, a hybrid technique was used to address floorpan vibration and the resulting radiated noise. The objective of this approach was to develop an optimized damping material application layout. This optimized layout balances the increased performance with the overall material volume, mass, and cost. The optimized damping material application developed resulted in a 3-5 dB reduction in the floorpan vibration level while saving 10% in material volume and mass. This optimized layout was validated on a body-in-white using a laser vibrometer. In addition, a new liquid applied material was also introduced with better damping characteristics.

Automotive engineering is taking a deeper look at the role of NVH engineering and design. Controlling the vehicle sound is one of the musts in designing successful automobiles today. While the focus is usually on powertrain noise, this report covers the concept of a new technology of dashmats. This new generation of dashmat is constructed of an absorptive layer, a barrier, and another absorptive layer (ABA). Typically, dashmats are placed inside the vehicle on the firewall between the powertrain and the driver. This dashmat blocks and absorbs powertrain noise as well as the vehicle background noise heard at the driver's ear. This report focuses on two types of competing dashmats-the light weight absorptive dashmat which acts by absorbing the sound rather than blocking it and the new generation of vehicle dashmat (ABA) which performs by blocking and absorbing the powertrain noise as well as the vehicle background noise.

The intent of this paper is to summarize the work of the V8 power plant intake manifold radiated noise study. In a particular V8 engine application, customer satisfaction feedback provided observations of existing unpleasant noise at the driver's ear. A comprehensive analysis of customer data indicated that a range from 500 to 800 Hz suggests a potential improvement in noise reduction at the driver's ear. In this study the noise source was determined using various accelerometers located throughout the valley of the engine and intake manifold. The overall surface velocity of the engine valley was ranked with respect to the overall surface velocity of the intake manifold. An intensity mapping technique was also used to determine the major component noise contribution. In order to validate the experimental findings, a series of analysis was also conducted. The analysis model included not only the plastic intake manifold, but also the whole powertrain.