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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.

The fuel consumption and emissions of diesel engines is strongly influenced by the injection rate pattern, which influences the in-cylinder mixing and combustion process. Knowing the exact injection rate is mandatory for an optimal diesel combustion development. The short injection time of no more than some milliseconds prevents a direct flow rate measurement. However, the injection rate is deduced from the pressure change caused by injecting into a fuel reservoir or pipe. In an ideal case, the pressure increase in a fuel pipe correlates with the flow rate. Unfortunately, real measurement devices show measurement inaccuracies and errors, caused by non-ideal geometrical shapes as well as variable fuel temperature and fuel properties along the measurement pipe. To analyze the thermal effect onto the measurement results, an available rate measurement device is extended with a flexible heating system as well as multiple pressure and temperature sensors.

This paper describes the development and application of the 1D thermo-fluid dynamic research code GASDYN to the simulation of a Lamborghini 12 cylinder, V 60°, 6.2 L automotive S.I. engine. The model has been adopted to carry out an integrated simulation (thermodynamic, fluid dynamic and chemical) of the engine coupled to its intake and exhaust manifolds, in order to predict not only the wave motion in the ducts and its influence on the cylinder gas exchange process, but also the in-cylinder combustion process and the pollutant emission concentration along the exhaust system. The gas composition in the exhaust pipe system is dictated by the cylinder discharge process, after the calculation of the combustion via a thermodynamic multi-zone model, based on a “fractal geometry” approach.

2-Butanone (C4H8O) is a promising alternative fuel candidate as a pure as well as a blend component for substitution in standard gasoline fuels. It can be produced by the dehydrogenation of 2-butanol. To describe 2-butanone's basic combustion behaviour, it is important to investigate key physical properties such as the laminar burning velocity. The laminar burning velocity serves on the one hand side as a parameter to validate detailed chemical kinetic models. On the other hand, especially for engine simulations, various combustion models have been introduced, which rely on the laminar burning velocity as the physical quantity describing the progress of chemical reactions, diffusion, and heat conduction. Hence, well validated models for the prediction of laminar burning velocities are needed. New experimental laminar burning velocity data, acquired in a high pressure spherical combustion vessel, are presented for 1 atm and 5 bar at temperatures of 373 K and 423 K.

To measure the fuel vapor concentration in an unsteady evaporating spray injected into nitrogen atmosphere, the exciplex-forming method, which produces spectrally separated fluorescence from the liquid and vapor phase, was applied in this study. Two experiments were conducted to investigate the qualitative and quantitative applicability of the technique in a high temperature and high pressure atmosphere during the fuel injection period. One is to examine the thermal decomposition of TMPD dopant at a high temperature and a high pressure nitrogen atmosphere during a short period of time. The other is to calibrate the relationship between fluorescence intensity and vapor concentration of TMPD at different vapor temperatures. And then, the qualitative measurement of fuel vapor concentration distributions in diesel sprays was made by applying the technique.

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.

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.

Increased torque values passing from engine to transmission have, increasingly become a problem regarding shaft misalignment. Engineers are restricted with regard to applying ISO standards when investigating bearing life cycles as they tend only to cover normal [radial thrust] load conditions. Depending on the application, the need has arisen for numerical models to determine reduction in normal life cycles due to abnormal running conditions. The Simulia Finite Element package Abaqus v6.7 provides trends in the deformations, contact pressures and their respective distribution. It was found the most efficient profile, with regards to a uniform contact pressure, under both radial and misaligned conditions is the toroidal profile.

The urea Selective Catalytic Reduction (SCR) exhaust system has been proved to be the reliable aftertreatment device with the capability of reducing tail pipe NOx emission by 75% to 90%, HC by 50% and Particulate Matter (PM) by 30%. Constrained by increasingly stringent packaging envelope, flow mixing in front of substrate is becoming one of the major concerns to achieve ideal performance of higher NOx conversion and lower ammonia (NH3) slip. Three dimensional CFD simulations are performed in current study to investigate flow mixing phenomenon in a SCR system. First, for a traditional tube injector with single or multiple nozzles, the effects of mass flow rates of injected NH3 and exhaust gas on flow mixing and pressure loss are investigated. Then, a concept of ring shape injector with multiple nozzles are initiated and built for 3-D CFD simulations. The comparisons of flow mixing index and injection pressure are made between two type injectors.

The main objective of the current paper was to investigate the fluid flow and pressure loss characteristics of DPF substrates with asymmetric channels utilizing 3-D Computational Fluid Dynamics (CFD) methods. The ratio of inlet to outlet channel width is 1.2. First, CFD results of velocity and static pressure distributions inside the inlet and outlet channels are discussed for the baseline case with both forward and reversed exhaust flow. Results were also compared with the regular DPF of same cell structure and wall material properties. It was found that asymmetrical channel design has higher pressure loss. The lowest pressure loss was found for the asymmetrical channel design with smaller inlet channels. Then, the effects of DPF length and filter wall permeability on pressure loss, flow and pressure distributions were investigated.

Three-dimensional behaviors of direct injection (D.I.) gasoline sprays were investigated using 2-D and 3-D particle image velocimetry (PIV) techniques. The fuel was injected with a swirl type injector for D.I. gasoline engines into a constant volume chamber in which ambient pressure was varied from 0.1 to 0.4 MPa at room temperature. The spray was illuminated by a laser light sheet generated by a double-pulsed Nd:YAG laser (wave length: 532 nm) and the succeeding two tomograms of the spray were taken by a high-resolution CCD camera. The 2-D and 3-D velocity distributions of the droplet cloud in the spray were calculated from these tomograms by using the PIV technique. The effects of the swirl groove flows in the injector and the ambient pressure on the structural behavior of the droplet cloud in the spray were also examined.

Traditional acoustic measurements inside any cavity have historically been conducted with a small number of microphones. By this means it is possible to gain information about parameters like frequencies, orders and sound pressures. However, a space-selective analysis is nearly impossible and it is not feasible to find the position of the sound sources in space in a practical way. While traditional beam forming systems with planar microphone arrays have enlarged the possibilities of acoustic measurements, they do not give comprehensive information about the sound sources in the entire vehicle interior. Therefore, the components of the Acoustic Camera of the GFal were extended by a spherical, acoustically transparent and omni-directional array. A new option is to map onto a common 3D-CAD-model of the object of interest, for instance a vehicle interior. The advantages and disadvantages of 2D- and 3D-mappings will be discussed in the paper.

This paper discusses the holistic approach of simulating a low pressure pump (LPP) including test stand flow dynamics. The simulation includes all lines and valves of the test stand representing realistic test operating conditions in the simulation. The capability to capture all line dynamics enables a robust design against resonances and delivers high-quality performance data. Comparison with actual test data agrees very well giving us confidence in the prediction capability of proposed method and CFD package used in the study. Despite the large spatial extent of the simulation domain, Simerics-MP+ (aka PumpLinx) is able to generate a feasible mesh, together with fast running speed, resulting in acceptable turn-around times. The ability to still model small gaps and clearance of the LPP very efficiently enables inclusion of realistic tolerances as experienced on hardware.

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.

Diesel Particulate Filters (DPF) are widely used to meet 2007 and beyond EPA Particulate Matter (PM) emissions requirements. During the soot loading process, soot is collected inside a porous wall and eventually forms a soot cake layer on the surface of the DPF inlet channel walls. A densely packaged soot layer and reduced pore size due to Particulate Matter (PM) deposition will reduce overall DPF wall permeability which results in increasing pressure drop across the DPF substrate. A regeneration process needs to be enacted to burn out all the soot collected inside the DPF. Soot mass is not always evenly distributed as the distribution is affected by the flow and temperature distribution at the DPF inlet. As a result, the heat release which is determined by the burn rate is locally dependent. High temperature gradients are often found inside DPF substrate as a result of these locally dependent burn rates.

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).