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Technical Paper

A Detailed Study on Differential Bearing Adjuster Ring Thread Engagement and Joint Strength, under Combined Bending and Axial Loading

Adjuster rings are used in commercial vehicle axle assembly to preload differential bearings and provide support in the axial direction. Adjuster along with the carrier and bearing cap combined to form a threaded joint. Adjuster with external threads engages with internal threads formed in carrier and bearing cap. Preload in differential assembly maintains the system rigidity and helps to maintain an optimized hypoid gear engagement. An adequate preload is important to achieve a desirable bearing life. Reduction in thread engagement at adjuster joint fully or partially will cause a reduction in preload and can lead to gear misalignment. This can cause severe durability concerns. In some cases, it is observed that under vehicle operating loads adjuster ring is backed off from its assembled condition by bending the split pin (split pin is, positive lock, used to maintain adjuster position) and adjuster threads were stripped off.
Technical Paper

A Diesel Oxidation Catalyst for Exhaust Emissions Reduction

The authors used a mass spectrometer to determine an SOF reduction mechanism of a diesel oxidation catalyst. The results indicate that SOF reduction lies in the catalytic conversion of high molecular organic matter to low molecular organic matter. And unregulated emissions are also reduced through this conversion. It is also found that the SOF reduction performance is highly dependent up on the condition of the wash coat. There is some limitation to improving diesel oxidation catalyst performance because of the sulfur content found in diesel fuel. Finally, the authors have determined what we think are the specifications of the presently best catalytic converter.
Technical Paper

A Digital Computer Method for the Prediction of Braking Performance of Trucks and Tractor-Trailers

The simulation of the longitudinal performance of trucks and articulated vehicles requires careful attention to tandem axle dynamics, the brake system model, and the tire model. The approach which was taken to these problems in a recently developed digital simulation is given. Results for the braking performance of an articulated vehicle and a straight truck are compared to empirical data. In addition, simulation results are given for the articulated vehicle equipped with a simple antiskid system.
Technical Paper

A Distributed Processor Approach for Marine Shift/Throttle Control

Several factors have driven the development of various electronic marine shift/throttle control systems in recent years. The benefits of marine electronic shift/throttle systems are increased cycle life, reduced maintenance requirements, and decreased installation concerns. Design considerations include selection of a microprocessor system, communication between nodes, operator feedback, and protocols for various mode selections. A recent development in marine electronic technology uses a distributed microprocessor approach that eliminates the negative factors associated with mechanical controls while actually improving operator feedback. The system's serial communication also allows for expansions into intelligent systems applications. This technology shows promise for use in industrial, automotive, and military applications.
Technical Paper

A Distributed Sensor for Sensing Dynamic Deflections

A distributed sensor is created to sense the rate of change in deflection of beam-like structures such as crane booms. This sensor will be useful in electrohydraulic compensation of boom deflections. The sensor is made of an array of strain-sensitive segments such as strain gages or piezoelectric film. In this example, segments of piezoelectric film convert strains on the surface of a vibrating beam into electrical outputs. These outputs are connected to low impedance signal conditioners. The output of the signal conditioners are then interpolated with a weighting vector that incorporates Lagrange polynomials, specified boundary conditions, and the desired location(s) of measurement. A simple linear combiner circuit combines the electrical outputs into the deflection velocity at the desired points.
Technical Paper

A Dual Fuel Injector for Diesel Engines

The authors designed and produced a new dual fuel injector that allows two different kinds of fuel to be injected. This injector contains both a throttle type nozzle and a hole type which are located coaxially. The injection timing as well as the fuel quantity can be controlled individually. The running test using two lines of gas oil brought a good reduction of NOx and exhaust smoke. The experiment using gas oil and alcohol also brought a satisfactory reduction of exhaust emission.
Technical Paper

A Dual-Fuel Model of Flame Initiation and Propagation for Modelling Heavy-Duty Engines with the G-Equation

We propose a novel dual-fuel combustion model for simulating heavy-duty engines with the G-Equation. Dual-Fuel combustion strategies in such engines features direct injection of a high-reactivity fuel into a lean, premixed chamber which has a high resistance to autoignition. Distinct combustion modes are present: the DI fuel auto-ignites following chemical ignition delay after spray vaporization and mixing; a reactive front is formed on its surroundings; it develops into a well-structured turbulent flame, which propagates within the premixed charge. Either direct chemistry or the flame-propagation approach (G- Equation), taken alone, do not produce accurate results. The proposed Dual-Fuel model decides what regions of the combustion chamber should be simulated with either approach, according to the local flame state; and acts as a “kernel” model for the G- Equation model. Direct chemistry is run in the regions where a premixed front is not present.
Training / Education

A Familiarization of Drivetrain Components

In this course, participants will be exposed to various methods that can be used to accomplish an efficient, robust & quiet running drivetrain. This course focuses on the terms, functions, nomenclature, operating characteristics and effect on vehicle performance for each of the drivetrain components. Participants will receive an introduction to the various components of the drivetrain, including the clutch or torque converter, manual or automatic transmission, driveshaft, axle, wheel ends, and brakes.
Technical Paper

A Fast Start-Up On-Board Diesel Fuel Reformer for NOx Trap Regeneration and Desulfation

This paper describes recent progress in our program to develop an emissions technology allowing diesel engines to meet the upcoming 2007/2010 regulations for NOx. At the heart of this technology is the ArvinMeritor Diesel Fuel Reformer that reforms the fuel, on-demand, on-board a vehicle. The fuel reformer uses plasma to partially oxidize a mixture of diesel fuel and air creating a highly reducing mixture of Hydrogen and Carbon monoxide. In a previous publication, we have demonstrated that using a reformate rich in H2 and CO to regenerate a NOx trap is highly advantageous compared to vaporized diesel fuel used conventionally. In this paper we present results and a strategy for performing desulfation of the traps using the fuel reformer. In contrast to vaporized diesel, which requires very high temperatures that fall outside the normal exhaust operating temperatures for diesel engines, desulfation was achieved at temperatures lower by more than 100 °C using the Plasma Fuel Reformer.
Technical Paper

A Feasibility Demonstration of an Electric Postal Delivery Vehicle

The technical and economic feasibility of an electric postal delivery vehicle is demonstrated and reported in this paper. Vehicle operational data are collected in a deployment of six prototype electric Long-Life Vehicles (ELLV) at postal sites in Torrance, California and Merrifield, Virginia, beginning in April, 1995. Eight months of data have been collected and are analyzed Extensive design trade studies and analyses are conducted to demonstrate the feasibility of achieving the maximum cost effectiveness of the ELLV Operating costs of the ELLV are compared to its internal combustion engine (ICE) counterpart.
Technical Paper

A Feature-Based Product Model for Valve Blocks

Valve blocks are the key parts in hydraulic systems. A feature-based product model is the foundation of the CAD/CAM system for valve blocks--VBCADAM. This paper mainly analyses the design procedure of valve blocks, the application of feature-based design and modeling, object-oriented approach in the development of VBCADAM, such as feature definition and classification, the frame description of features, structure of product model and also the application of the product model in VBCADAM.
Technical Paper

A Flexible Hydraulic System for a Self-Propelled Forage Harvester

A new hydraulic system was developed using off-the-shelf components to gain lower effort steering, push-button machine function controls, and improved reliability. The ability to alter or add to the system (flexibility) is a requirement. The hydraulic control requirements for this vehicle are similar to other self-propelled machines. The inherent flexibility of this system may make it adaptable, at least in part, to other vehicles.
Technical Paper

A Four Wheel Drive Transfer Case with Internal VR Motors for Shifting and Clutch Actuation

A modular, fully automatic transfer case was designed and developed using electronically controlled inboard electric motors for shifting the high - low range and automatically shifting into four wheel drive for control of torque to the front axle. Compact modular construction was used to minimize weight, to provide for either reduction or overdrive, and for easy adaptation to different transmissions.
Technical Paper

A Fully Integrated Partial Flow Filter with a Specialized and Unique Engine Management System to Meet Tier 4 Emission Legislations

Partial flow filters (PFF) are devices that can capture particulate matter (PM) for a period of time sufficient for its catalytic oxidation. The filter consists of alternating layers of corrugated metal foil and porous sintered metal fleece which captures the particulates. The captured particles are then re-generated passively by nitrogen dioxide (NO2) produced by the oxidation of NO on a diesel oxidation catalyst (DOC) placed before the filter. The filter's robust design and the ability to operate without any maintenance, i.e. no vehicle downtime, have led to an increasing demand for both heavy duty (HD) and light duty (LD) retrofit applications worldwide. Unlike diesel particulate filter (DPF), the PFF will not plug once filled with soot to its maximum capacity in the absence of passive regeneration (low load and low exhaust temperature conditions). Instead, the PM conversion efficiency will gradually decrease, allowing PM emissions to pass through.
Technical Paper

A Generalized Isobaric and Isochoric Thermodynamic Scavenging Model

As a non-predictive model of the scavenging process, a generalized thermodynamic model has been suggested. This model can give a thermodynamic description for any possible scavenging process. Having specified a history of the scavenging process, this model is suitable for all scavenging systems including cross, loop and uniflow scavenging schemes. For the simplified isobaric and isochoric model with respectively constant coefficients of intake and discharge proportions during different scavengine phases, analytical solutions for this model have been obtained. From these, all existing models with the isobaric and isochoric assumptions can be derived.
Technical Paper

A Giant Tractor Shovel - The 475

Production cost analyses show a potential economic advantage for thegiant loaders on large jobs. This paper presents a cost comparison between the Model 475 tractor shovel, a smaller tractor shovel, and a swing shovel. Evolutionary events and designs leading to the creation of the 475 are presented and discussed. Design considerations and specific features of this unit are pointed out. Some of these are: loader linkage design, hollow boom construction, split hydraulic system, and a hydraulic power assist for operator controls. Prototype testing and changes are discussed and explained.
Journal Article

A Guide to Uncertainty Quantification for Experimental Engine Research and Heat Release Analysis

Abstract Performing an uncertainty analysis for complex measurement tasks, such as those found in engine research, presents unique challenges. Also, because of the excessive computational costs, modeling-based approaches, such as a Monte Carlo approach, may not be practical. This work provides a traditional statistical approach to uncertainty analysis that incorporates the uncertainty tree, which is a graphical tool for complex uncertainty analysis. Approaches to calculate the required sensitivities are discussed, including issues associated with numerical differentiation, numerical integration, and post-processing. Trimming of the uncertainty tree to remove insignificant contributions is discussed. The article concludes with a best practices guide in the Appendix to uncertainty propagation in experimental engine combustion post-processing, which includes suggested post-processing techniques and down-selected functional relationships for uncertainty propagation.
Technical Paper

A Heavy Duty 18 Speed Transmission

The development of a range type transmission that splits both the low and the high range has led to some unexpected benefits of simpler and easier shifting. Employing fewer and simpler parts, an eighteen speed transmission has been developed that allows pre-selection of all splitter shifts and eliminates special shift sequencing that has been required on traditional products. Spin-off of these techniques can be extended into many other configurations that are popular in the trucking industry.
Journal Article

A High Efficiency, Dilute Gasoline Engine for the Heavy-Duty Market

A 13 L HD diesel engine was converted to run as a flame propagation engine using the HEDGE™ Dual-Fuel concept. This concept consists of pre-mixed gasoline ignited by a small amount of diesel fuel - i.e., a diesel micropilot. Due to the large bore size and relatively high compression ratio for a pre-mixed combustion engine, high levels of cooled EGR were used to suppress knock and reduce the engine-out emissions of the oxides of nitrogen and particulates. Previous work had indicated that the boosting of high dilution engines challenges most modern turbocharging systems, so phase I of the project consisted of extensive simulation efforts to identify an EGR configuration that would allow for high levels of EGR flow along the lug curve while minimizing pumping losses and combustion instabilities from excessive backpressure. A potential solution that provided adequate BTE potential was consisted of dual loop EGR systems to simultaneously flow high pressure and low pressure loop EGR.