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In this paper, we present a design and control methodology of an innovated structure of switching synchronous motor. This control strategy is based on the pulse width modulation technique imposing currents sum of a continuous value and a value having a shape varying in phase opposition with respect to the variation of the inductances. This control technology can greatly reduce vibration of the entire system due to the strong fluctuation of the torque developed by the engine, generally characterizing switching synchronous motors. A systemic design and modelling program is developed. This program is validated following the implementation and the simulation of the control model in the simulation environment Matlab-Simulink. Simulation results are with good scientific level and encourage subsequently the industrialization of the global system.

An advanced low heat rejection engine concept has successfully completed a 100 hour endurance test. The combustion chamber components were insulated with thermal barrier coatings. The engine components included a titanium piston, titanium headface plate, titanium cylinder liner insert, M2 steel valve guides and monolithic zirconia valve seat inserts. The tribological system was composed of a ceramic chrome oxide coated cylinder liner, chrome carbide coated piston rings and an advanced polyolester class lubricant. The top piston compression ring Included a novel design feature to provide self-cleaning of ring groove lubricant deposits to prevent ring face scuffing. The prototype test engine demonstrated 52 percent reduction in radiator heat rejection with reduced intake air aftercooling and strategic forced oil cooling.

A drivetrain model incorporating detailed crankshaft and drivetrain dynamics has been incorporated into an unsteady gas dynamic computer simulation of a single-cylinder two-stroke engine. This study examines the change in predicted engine performance caused by relaxing the conventional assumption of constant crankshaft velocity, and a comparison of results is presented. Relaxing the assumption changed the predicted brake mean effective pressures by over 10%. Experimental validation of the simulation involved mounting an engine to a test bed and driving an inertia wheel through a fully characterized drivetrain. A high-speed data acquisition system measured signals from a position encoder mounted on the crankshaft and from a non-contact torque transducer. The time and position data were used to calculate instantaneous crankshaft speed, and these results were compared to the predicted profiles. Simulation results and experimental measurements are presented and discussed.

Transfer path analysis is a powerful tool to support the vehicle NVH development. On the one hand it is a fast method to gain an overview of the complex interplay in the vehicle noise generation process. On the other hand it can be used to identify critical noise paths and vehicle components responsible for specific noise phenomena. FEV has developed several tools, which are adapted to the considered noise phenomena: Powertrain induced interior noise and vibration is analyzed by VINS (Vehicle Interior Noise Simulation), which allows the deduction of improvement measures fast enough for application in the accelerated vehicle development process. Further on vehicle/powertrain combinations not realized in hardware can be evaluated by virtual installation of the powertrain in the vehicle, which is especially interesting in the context of engine downsizing from four to three or six to four cylinders.

The experience accumulated with a prototype 1000 HP diesel electric tractor since 1969 is described. The new 1500 HP V220 diesel electric tractors are described along with some of the initial operation of these two units. Experience with the initial 1000 HP unit and the two 1500 HP tractors confirm the necessity of additional testing and experimentation to refine the design to get greater productivity with reduced operator fatigue. The unpredictability of the load and operating surface are major problems that present a real challenge to the engineer.

In a running engine, various impacts are excitation sources for structural vibrations and engine noises. Engine noises are classified, depending on their excitation sources, into the combustion noise, the combustion induced mechanical noise and the mechanical noise. It is difficult to measure such noises separately because some impacts occur closely in time and space. In this paper, a transient noise generation model of an engine was proposed considering vibration and its damping of engine structure. The present model was verified through the single explosion excitation experiment for a stationary engine. Using the noise generation model, the combustion noise was separated from the total noise radiating from a running four-stroke gasoline engine for motorcycles. It was found that the combustion noise had larger power at lower frequencies than higher frequencies. However, its contribution to the total engine noise was relatively small.

This paper presents a summary of body structural analysis applied to the 1989 Suzuki Sidekick/Geo Tracker at various stages of development and design. The structure analysis techniques were applied previously to rigidity, vibration, strength, crashworthiness and optimization. The studies confirm that the CAE technique for body structure analysis is more beneficial if it is utilized in the earlier structure development stages particularly for vibration and crashworthiness. Through the extensive use of the structural analysis technique in conjunction with the experiment, the design concept of the Sidekick/Tracker body has been optimized to a most extent.

A sheet of laser light from a frequency tripled Nd-YAG laser approximately 200μm thick is shone through the combustion chamber of a single cylinder, direct injection internal combustion engine. The injected decane contains exciplex—forming dopants which produce spectrally separated fluorescence from the liquid and vapor phases. The fluorescence signal is collected through a quartz window in the cylinder head and is imaged onto a diode array camera. The camera is interfaced to a microcomputer for data acquisition and processing. The laser and camera are synchronized with the crankshaft of the engine so that 2—D images of the liquid and vapor phase fuel distributions can be obtained at different times during the engine cycle. Results are presented at 600, 1200 and 1800 rpm, and from the beginning to just after the end of injection. The liquid fuel traverses the cylinder in a straight line in the form of a narrow cone, but does not reach the far wall in the plane of the laser sheet.

The work presented here seeks to compare different means of providing scavenging systems for an automotive 2-stroke engine. It follows on from previous work solely investigating uniflow scavenging systems, and aims to provide context for the results discovered there as well as to assess the benefits of a new scavenging system: the reverse-uniflow sleeve-valve. For the study the general performance of the engine was taken to be suitable to power a medium-duty truck, and all of the concepts discussed here were compared in terms of indicated fuel consumption for the same cylinder swept volume using a one-dimensional engine simulation package. In order to investigate the sleeve-valve designs layout drawings and analysis of the Rolls-Royce Crecy-type sleeve had to be undertaken.

In this work, the authors assess the potential of the 2-stroke concept applied to Range Extender engines, proposing 3 different configurations: 1) Supercharged, Compression Ignition; 2) Turbocharged, Compression Ignition; 3) Supercharged, Gasoline Direct Injection. All the engines feature a single power cylinder of 0.49l, external air feed by piston pump and an innovative induction system. The scavenging is of the Loop type, without poppet valves, and with a 4-stroke like lubrication system (no crankcase pump). Engine design has been supported by CFD simulations, both 1D (engine cycle analysis) and 3D (scavenging, injection and combustion calculations). All the numerical models used in the study are calibrated against experiments, carried out on engines as similar as possible to the proposed ones.

The demands for comfort and a cleaner environment have been increasing for the past years for motorcycle as well as car manufacturers. With the need to decrease the time-to-market, there is a clear drive to apply CAE-based methods in order to evaluate new designs and to propose design changes that solve any identified problems. More specifically, the demands on the comfort of the rider are not only related to ride & handling and vibration levels(1), but also to the noise levels generated by the motorcycle. This paper presents the virtual modeling of one-cylinder engine of a motorcycle that identifies the mechanism behind the generation of an annoying noise. Furthermore, different possible design changes were evaluated in order to solve the problem. A combined experimental and numerical approach was followed to achieve this. Experiments were used to identify important parameters that determine the engine behavior and thus are critical for the modeling of such an engine.

The present study compares the NVH performance of three different materials used on cam covers in automobiles, Aluminum (Al), Magnesium (Mg) and Thermoplastic (TP). The cam cover design used for this comparison was the 2004 Nissan Maxima 3.5L production cam cover which is made of a thermoplastic (TP). The Al and Mg covers for this study were created by sandcast, due to time constraints, via laser scanning techniques using the 2004 Nissan Maxima 3.5L production thermoplastic cover design. Note that sand-cast covers generally provide a less quiet sound field than the standard casting method. The Nissan production cover comes with a production baffle made of a similar material as the cover. Testing was conducted with and without the production baffle for all covers. The study was conducted for the production boundary condition of a non-isolated cover and a Freudenberg-NOK (FNGP) partially isolated cover. Isolated bolt assemblies using elastomeric grommets were used to isolate the cover.

This paper describes a new concept for a Ford GT instrument panel (IP) based on structural magnesium components, which resulted in what may be the industry's first structural IP (primary load path). Two US-patent applications are ongoing. Design criteria included cost, corrosion protection, crashworthiness assessments, noise vibration harshness (NVH) performance, and durability. Die casting requirements included feasibility for production, coating strategy and assembly constraints. The magnesium die-cast crosscar beam, radio box and console top help meet the vehicle weight target. The casting components use an AM60 alloy that has the necessary elongation properties required for crashworthiness. The resulting IP design has many unique features and the flexibility present in die-casting that would not be possible using conventional steel stampings and assembly techniques.

The High Voltage Power Distribution Unit (PDU) is constructed of magnesium in support of Fuel Cell Electric Vehicle (FCEV) weight reduction efforts. The PDU distributes and controls a nominal 75 kilowatts of power generated by the Fuel Cell, the primary source of High Voltage power, to all the vehicle loads and accessories. The constraints imposed on the design of the PDU resulted in a component highly susceptible to general and galvanic corrosion. Corrosion abatement was the focus of the PDU redesign. This paper describes the redesign efforts undertaken by Ford personnel to improve the part robustness and corrosion resistance.

To effectively utilize larger trucks (85 ton and up), open-pit mines and quarries need a larger front-end loader with high reliability and performance. This paper describes the design approach and tests carried out to design 21 cubic yard 580 PAY® loader to meet these requirements. Long fatigue life of structures was obtained by use of full penetration welds. New concept for power control was designed to effectively distribute power between hydraulics and drive train. Spring applied - pressure released brakes were designed into the axle. Tests were carried out in our laboratory and proving grounds to determine performance and reliability.

This study focuses on variable amplitude loadings applied to automotive chassis parts experiencing carmaker’s specific proving grounds. They are measured with respect to time at the wheel centres and composed of the six forces and torques at each wheel, within the standard vehicle reference frame. In the scope of high cycle fatigue, the loadings considered are supposedly acting under the structure yield stress. Among the loadings encountered during the vehicle lifetime, two classes stand out: Driven Road: loads measured during the vehicle manoeuvre; Random Road: loads mainly coming from the road asperity. To separate both effects, a frequency decomposition method is proposed before applying any lifetime assessment methods. The usual Rainflow counting method is applied to the Driven Road signal. These loadings, depending on the vehicle dynamics, are time-correlated. Thus, the load spectra is set only thanks to the vehicle accelerations time-measurement.

In order to reproduce heavy bass with a small diameter loudspeaker for automotive use similar to the intensity and low distortion of a home-use Hi-Fi system, a large volume velocity must be obtained. This is done by lowering the minimum resonant frequency of system and by linearly expanding the amplitude range of diaphragm. We have developed a 3-D woofer system using a centering suspension that consists of four tubes of square cross-section continuously laid in the circumferential direction and a cone suspension that has V-shaped pleats in both of the circumferential and diameter directions for the vibration system. The results are good acoustic characteristics in an automotive cabin that are low in distortion with high output in the low frequency range up to 100Hz.

In the design and development of modern cars with respect to comfort, silence and safety, state of the art experimental modal analysis is one of the essential development tools. Due to the large amount of degrees of freedom of such a large and complex system like a car with all its components, a complete simulation by FEM can not be realised easily and requires an enormous expenditure of work and calculations. In addition the simulations are based on assumed system parameters and thus the vibration behaviour of the resulting prototypes often is not completely identical to the simulated model. In contrast to conventional measurements with accelerometers, the 3-D Scanning Vibrometer enables fast and efficient non-contact measurements of the in-plane and out-of-plane vibration behaviour at all optical accessible surfaces. The method easily allows to increase the number of measured points to obtain a high measurement point density.

Multi-layer steel (MLS) cylinder head gaskets are becoming more widely used to seal an engine. Therefore, it is important to understand the interaction between the engine head, block and head gasket. While experimental methods for determining necessary gasket tightening loads and experimental data relating some gasket design parameters to failure are available, it is very costly and time consuming. A numerical method, such as the finite element (FE) method, has proven to be very useful and efficient in aiding gasket design. A 3D engine FE analysis can predict a number of parameters. Of particular interest are the motion as well as the contact profile of the head, block and gasket. This information, usually difficult or impossible to obtain from a 2D FE analysis, can be used to predict the two most common failure modes of a gasket, fatigue crack and leakage.

The present study deals with the reduction of fluid vibrations by dissipating the kinetic energy in a closed vibrating container partly filled using vertical slotted obstacles. The effect of the barriers on the liquid vibration inside a closed container exposed to a harmonic excitation is numerically studied. A single vertical slotted barrier (SVSB) and multivertical slotted barrier (MVSB) systems are considered for different liquid levels. The 3D liquid domain with the tank and the barrier as boundaries is modelled and solved numerically using ANSYS-CFX software. The reduction in pressures on the walls and the ceiling of the tank due to the influences of the slot size and numbers were evaluated to optimize the size and the numbers of the slots. The numerical approach shows an ability to simulate the nonlinear behavior of the liquid vibration when using vertical slotted barriers (VSB).