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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.

This work deals with the CAE simulation of the behaviour of a belt employed in a CVT transmission of a large displacement scooter engine. Both FEM and MBS simulations were performed, in order to estimate the dynamic loads acting on the component and the stress state the belt is subject to. The MBS simulations were backed up by simple FEM tests performed in order to estimate the elastic properties of elementary portions of the belt. The MBS system comprised the belt and the two pulleys. As a result, the force components the pulleys exert on the belt were calculated. FEM non-linear analyses were performed in order to estimate the stress state the belt experiences. The belt's both manufacturing and working conditions were simulated.

This paper introduces research work on 1-D model of Roots type supercharger with helical gears using 1-D simulation tool. Today, passenger car engine design follows approach of downsizing and the reduction of number of engine cylinders. Superchargers alone or their combination with turbochargers can fulfill low-end demands on engine torque for such engines. Moreover, low temperature combustion of lean mixture at low engine loads becomes popular (HCCI, PCCI) requiring high boost pressure of EGR/fresh air mixture at low exhaust gas temperature, which poses too high demands on turbocharger efficiency. The main objective of this paper is to describe Roots charger features and to amend Roots charger design.

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 Ford Ranger will be a domestically built, small pickup truck engineered to many design objectives typical of a fullsize pickup, yet with four cylinder engine fuel efficiency. Ranger is a full-function on-and-off road pickup truck with a uniquely smooth ride and a capacity to carry up to a 725.7 kg. (1600 lb.) payload. The truck features a three passenger body-on-frame cab and a double wall pickup box with provision for 1.2m × 2.4m (4 ft. × 8 ft.) sheets of construction material. Featured in this comprehensive paper are the engineering highlights and innovations contributing to the accomplishment of these Small Truck objectives.

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.

Motor thermal management of electric vehicles (EVs) is becoming more significant due to its close relations to vehicle aerodynamic performance and power consumption, while computer aided engineering (CAE) plays an important role in its development. A 1D-3D coupled model is established to characterize transient thermal performance of the motor in an electric vehicle on a high performance computer (HPC) platform. The 1D motor thermal management model is integrated with the 1D powertrain model, and a 3D thermal model is established for the motor, while online data exchange is realized between the 1D and 3D models. The 1D model gives boundaries such as inlet coolant temperature, mass flowrate and motor heat generation to the 3D model, while the 3D model gives back boundaries such as heat transfer to coolant simultaneously. Transient simulations are performed for the 140kph(20°C) driving cycle, and the model is calibrated with experimental data.

Thermal management in electric vehicles (EVs) has attracted more attention due to its increasing significance, and computer aided engineering (CAE) plays an important role in its development. A 1D-3D online coupling approach is proposed to completely characterize transient thermal performance of an electric vehicle on a high performance computer (HPC) platform. The 1D thermal management model, consisting of air conditioning, motor cooling and battery cooling systems, is integrated with the 1D control strategy model and powertrain model consisting of motor, battery, driver and vehicle models. The 3D model is established for the air flow around the full vehicle and through its underhood. The 3D model gives boundaries such as heat exchanger air flowrates and heat flows on some component surfaces to the 1D model, while 1D gives back boundaries such as heat exchanger heat loads, component surface temperatures and fan speed simultaneously.

In order to investigate the soot formation process in a diesel spray flame, simultaneous imaging of soot precursor and soot particles in a transient spray flame achieved in a rapid compression machine was conducted by laser-induced fluorescence (LIF) and by laser-induced incandescence (LII) techniques. The 3rd harmonic (355nm) and the fundamental (1064nm) laser pulses from an Nd:YAG laser, between which a delay of 44ns was imposed by 13.3m of optical path difference, were used to excite LIF from soot precursor and LII from soot particles in the spray flame. The LIF and the LII were separately imaged by two image-intensified CCD cameras with identical detection wavelength of 400nm and bandwidth of 80nm. The LIF from soot precursor was mainly located in the central region of the spray flame between 40 and 55mm (270 to 370 times nozzle orifice diameter d0) from the nozzle orifice. The LII from soot particles was observed to surround the soot precursor LIF region and to extend downstream.

The two-dimensional distribution of a soot cloud in an unsteady spray flame in a rapid compression machine(RCM) was visualized using the laser sheet scattering technique. A 40 mm x 50 mm cross section on the flame axis was illuminated by a thin laser sheet from a single pulsed Nd:YAG laser(wavelength 532 nm). Scattered light from soot particles was taken by a CCD camera via a high speed gated image intensifier. The temporal variation of the scattered light images were presented with the injection pressure as a parameter. The results showed that scattered light was intense near the periphery of the flame tip and that the scattered light becomes weaker significantly and disappears fast after the end of injection as injection pressure is increased. This technique was also applied to the visualization of the two-dimensional distribution of liquid droplets in the non-evaporating spray to correlate it with the soot concentration distribution.

A sheet of laser light from a frequency-doubled Nd-YAG laser (λ = 532 nm) approximately 150 μm thick is shone through the cylinder of a single cylinder internal combustion engine. The light scattered by the fuel spray is collected through a quartz window in the cylinder and is imaged on a 100 × 100 diode array camera. The signal from the diode array is then sent to a microcomputer for background subtraction and image enhancement. The laser pulse is synchronized with the crank shaft of the engine so that a picture of the spray distribution within the engine at different times during injection and the penetration and development of the spray may be observed. The extent of the spray at different positions within the chamber is determined by varying the position and angle of the laser sheet with respect to the piston and the injector.

Two dimensional visualization of a pulsating, hollow-cone spray was performed in a motored, ported, high swirl, cup-in-head I.C. engine, using exciplex-forming dopants in the fuel, which produced spectrally separated fluorescence from the liquid and vapor phases. Illumination was by a laser sheet approximately 200 µm thick from a frequency tripled Nd:YAG laser, and image acquisition was by a 100 × 100 pixel diode array camera interfaced to a personal computer. Liquid and vapor phase fuel distributions are reported for engine speeds of 800 rpm and 1600 rpm, over a crankangle range spanning the injection event and subsequent evaporation and mixing. The beginning of injection was at 33° BTDC at 800 rpm and 47° BTDC at 1600 rpm. At 800 rpm, the spray angle is narrower than the 60° poppet angle, as expected from previous observations in a near-quiescent spray chamber.

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.

Structure enhancement based on data monitored in a traditional side impact evaluation is primarily a trial and error exercise resulting in a large number of computer runs. This is because how the structure gets loaded and the degree of contribution of local structural components to resist the impact while absorbing energy during a side collision is not completely known. Developing real time complete load profiles on a body side during the time span of an impact is not an easy task and these loads cannot be calculated from that calculated at the barrier mounting plate. This paper highlights the load distribution, calculated by a procedure using computer aided engineering (CAE) tools, on a typical 2-door vehicle body side when struck by moving deformable barriers used in the insurance institute for highway safety (IIHS), EuroNCAP and LINCAP side impact evaluations.

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.

This paper documents a joint development process between General Motors and Dow Automotive to improve primary body structure frequencies on the GM family of midsize vans by utilizing cavity-filling structural foam. Optimum foam locations, foam quantity, and foam density within the body structure were determined by employing both math-based modeling and vehicle hardware testing techniques. Finite element analysis (FEA) simulations of the Body-In-White (BIW) and “trimmed body” were used to predict the global body structure modes and associated resonant frequencies with and without structural foam. The objective of the FEA activity was to quantify frequency improvements to the primary body structure modes of matchboxing, bending, and torsion when using structural foam. Comprehensive hardware testing on the vehicle was also executed to validate the frequency improvements observed in the FEA results.

In October 1999, General Motors contracted Dana Corporation to manufacture an all-aluminum spaceframe for the 2006 Chevrolet Corvette Z06. Corvette introduced its first ever all-aluminum frame (see Figure 1) to the world at the 2005 North American International Auto Show (NAIAS) in Detroit, Michigan. The creation of this spaceframe resulted in a significant mass reduction and was a key enabler for the program to achieve the vehicle level performance results required for a Z06 in an ever-growing market. Dana Corporation leveraged ALCOA's (Aluminum Company of America) proven design capabilities while incorporating new MIG welding, laser welding, Self-Pierce Riveting (SPR), and full spaceframe machining to join General Motors (GM) Metal Fabrication Division's (MFD) hydroformed rails to produce the Corvette Z06's yearly requirement of 7000 units. This paper describes the technologies utilized throughout the assembly line and their effect on the end product.

The 2013 SRT Viper Carbon Fiber X-Brace, styled by Chrysler's Product Design Office (PDO), is as much of a work of art as it is an engineered structural component. Presented in this paper is the design evolution, development and performance refinement of the composite X-Brace (shown in Figure 1). The single-piece, all Carbon Fiber Reinforced Plastic (CFRP) X-Brace, an important structural component of the body system, was developed from lightweight carbon fiber material to maximize weight reduction and meet performance targets. The development process was driven extensively by virtual engineering, which applied CAE analysis and results to drive the design and improve the design efficiency. Topology optimization and section optimization were used to generate the initial design's shape, form and profile, while respecting the package requirements of the engine compartment.

On January 14, 2004 President George W Bush outlined a new vision for NASA that has humans venturing back to the moon by 2020. With this ambitious goal, new tools and models have been developed to help define and predict the amount of space radiation astronauts will be exposed to during transit and habitation on the moon. A representative scenario is used that includes a trajectory from LEO to a Lunar Base, and simplified CAD models for the transit and habitat structures. For this study galactic cosmic rays, solar proton events, and trapped electron and proton environments are simulated using new dynamic environment models to generate energetic electron, and light and heavy ion fluences. Detailed calculations are presented to assess the human exposure for transit segments and surface stays.

The distribution of spray droplet sizes plays a pivotal role in internal combustion engines, directly affecting fuel-air mixing, evaporation, and combustion. To gain a precise understanding of droplet size distribution in a two-dimensional space, non-intrusive optical diagnostics emerge as a highly effective method. In the current investigation, two-dimensional (2D) diesel spray droplet sizes mapping using a simultaneous combination of planar laser-induced fluorescence (PLIF) and Mie-scattering techniques is introduced. The assessment of droplet diameter relies on the interplay between fluorescent and scattered light intensities which correspond the light based on volumetric droplets and surface area of the droplets. This calculation is made possible through the LIF/Mie technique. However, traditional LIF/Mie methods are plagued by inaccuracies arising from multiple light scattering.