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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.

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.

During the past decades the public acceptance of the actual environmental legislation has gradually turned into an active support of the same. Test methods have anyhow become more cost heavy and time consuming, underlining the need of simplified tests with reasonable correlation to the legal methods. Generally, the emissions under static and semistatic load conditions are gradually eliminated, why the heavy pollution now comes from transient periods of the driving pattern. Consequently a transient test procedure must satisfy the quality requirements on a short test applicable to vehicles from cars to heavy trucks and busses. The INertia COLLection system described here is developed to enable low cost and well repeatable measurements of the emission characteristics of engine systems in light and heavy vehicles under transient load. The system is easy to adopt and does not need any chassis dynamometer.

Recently, significant focus and development effort has been dedicated toward in-vehicle networking. This effort includes work on behalf of the American Trucking Association (ATA), the Society of Automotive Engineers (SAE), the International Standards Organization (ISO), and independent developments by automotive and semiconductor manufacturers. In-vehicle networking extends, as a result, beyond passenger cars into heavy truck, military, and construction vehicles. In the course of these developments, the benefits of networking have been examined and networking is perceived as having significant benefits, resulting in production and custom development [1, 2, 3]. The Controller Area Network (CAN) is a high-performance serial communication solution which has been designed to meet the requirements for the broad range of applications and has now progressed from a specification to a product.

Combustion control strategy for high efficiency and low emissions in a heavy duty (H D) diesel engine was investigated experimentally in a single cylinder test engine with a common rail fuel system, EGR (Exhaust Gas Recirculation) system, boost system and retarded intake valve closing timing actuator. For the operation loads of IMEPg (Gross Indicated Mean Effective Pressure) less than 1.1 MPa the low temperature combustion (LTC) with high rate of EGR was applied. The fuel injection modes of either single injection or multi-pulse injections, boost pressure and retarded intake valve closing timing (RIVCT) were also coupled with the engine operation condition loads for high efficiency and low emissions. A higher boost pressure played an important role in improving fuel efficiency and obtaining ultra-low soot and NOx emissions.

A multi-year Power System R&D project was initiated with the objective of developing an off-road hybrid heavy-duty concept diesel engine with front end accessory drive-integrated energy storage. This off-road hybrid engine system is expected to deliver 15-20% reduction in fuel consumption over current Tier 4 Final-based diesel engines and consists of a downsized heavy-duty diesel engine containing advanced combustion technologies, capable of elevated peak cylinder pressures and thermal efficiencies, exhaust waste heat recovery via SuperTurbo™ turbocompounding, and hybrid energy recovery through both mechanical (high speed flywheel) and electrical systems. The first year of this project focused on the definition of the hybrid elements using extensive dynamic system simulation over transient work cycles, with hybrid supervisory controls development focusing on energy recovery and transient load assist, in Caterpillar’s DYNASTY™ software environment.

A knowledge-based system for agricultural tillage equipment selection and management is presented. There are ten tillage systems suitable for corn and soybean production in Ontario. These systems manipulate the soil by different amounts resulting in varying levels of soil degradation, crop yields, and weed problems. Many factors, such as soil characteristics, climate, farm economics, and environmental impact make the selection of the most appropriate tillage practice a difficult task. Except for mouldboard plough, few farmers have experience operating and managing these tillage systems. Knowledge and information obtained from three experts is incorporated into the knowledge-based computer program to aid farmers in the selection and management of tillage systems. Selection criteria included in the program are environmental impact, management difficulty, economic return, and energy output/input ratio.

The Organic Rankine Cycle (ORC) has proven to be a promising technology for Waste Heat Recovery (WHR) systems in heavy duty diesel engine applications. However, due to the highly transient heat source, controlling the working fluid flow through the ORC system is a challenge for real time application. With advanced knowledge of the heat source dynamics, there is potential to enhance power optimization from the WHR system through predictive optimal control. This paper proposes a look-ahead control strategy to explore the potential of increased power recovery from a simulated WHR system. In the look-ahead control, the future vehicle speed is predicted utilizing road topography and V2V connectivity. The forecasted vehicle speed is utilized to predict the engine speed and torque, which facilitates estimation of the engine exhaust conditions used in the ORC control model.

This paper presents some of the history of the Spacemetal process development; a discussion of the core forming machine, a description of the welder where corrugated core and facing sheets are joined; the quality control process employed for inspecting the finished product; and some of the material properties and applications. FOREWORD Development of a production process and the machines for fabrication of a resistance welded steel sandwich was made by Missile Division, North American Aviation, Inc. Development was carried forward under contract AF 33(600)-26154 from the Manufacturing Methods Branch, Industrial Resources Division of the Air Materiel Command USAF.

METHOD of selecting sbaetiasfraicntogrsy for the transmissions and final drives of pneumatic-tired tractors that depends on a knowledge of average operating conditions is reported by John Borland. The well-known method of rating bearings on a fatigue basis is, according to tests carried out by Mr. Borland, a reasonably accurate way of predicting bearing life when loading conditions are definitely established. However, the tables that have been compiled by the bearing manufacturers are satisfactory for determining bearing life only of bearings subjected to a constant load at a constant speed. Since tractor transmissions are subjected to as many different loading conditions as there are speed changes provided in the tractor, tractor transmission bearings cannot be selected directly from these tables. They must be used in conjunction with the formula for determining a factor called weighted life.

The traditional approach to materials selection is to compare the results of direct substitution of alternative materials on an individual part-by-part basis. The engineer then frequently faces so many design constraints that use of a new material is infeasible. This approach also precludes redesign to optimize the characteristics of new materials. A methodology is presented which facilitates the consideration of a large system comprised of many components. The management science technique of “multi-attribute utility analysis” is applied as a tool for use by automotive design engineers. Attributes include capital cost, piece cost, weight, design flexibility and corrosion resistance. The results serve as a decision making tool to determine which design provides the greatest overall value. Also, the results may be used as a design aid to quantify desirable tradeoffs between attributes, thus pointing the way towards optimal redesign.

This paper describes the design strategy adopted for developing a new high performance actuation system referred to as the ElectroHydraulic Actuator (EHA). The design approach can be divided into fives phases that include: pre-conceptual analysis, conceptual design, preliminary design, detailed design and, integration and test. An important aspect of the design process is the use of modeling and simulation for the analysis, sizing and selection of off-the-shelf parts, and for the detailed design of new custom made components. EHA is based on hydrostatic transmission. It is a unique device with its own characteristics and requires hydraulic components that are specifically tailored to its needs. A prototype of EHA has been produced and has demonstrated an extremely high level of performance. The performance of this prototype complies with design requirements and validates the chosen design approach.

Abstract One of the key factors for accurate mass burn fraction and energy conversion point calculations is the accuracy of the compression ratio. The method presented in this article suggests a workflow that can be applied to determine or correct the compression ratio estimated geometrically or measured using liquid displacement. It is derived using the observation that, in a motored engine, the heat losses are symmetrical about a certain crank angle, which allows for the derivation of an expression for the clearance volume [1]. In this article, a workflow is implemented in real time, in a current production engine indicating system. The goal is to improve measurement data quality and stability for the energy conversion points calculated during measurement procedures. Experimental and simulation data is presented to highlight the benefits and improvement that can be achieved, especially at the start of combustion.

Vehicle manufacturers strive hard to achieve best in class fuel economy. Apart from light weighting of the structures, driveline optimization and reduction of tire rolling resistance, tapping of parasitic losses is also important and helps to optimize the design of auxiliary power consuming systems. One of such system studied in this work is power steering system. The effect of parasitic losses on fuel economy is predominant for small commercial vehicle compare to heavy vehicles. The evaluation of deterioration in the fuel economy due to implementation of power steering system on one of the small commercial vehicle is carried out using multiple virtual simulation tools. Virtual route profile is modelled using longitude, latitude and altitude data captured through GPS and steering duty cycle is mapped in terms of steering rotation angle. A system level model of hydraulic power steering system is developed.

In an effort to reduce the design cycle time and to meet increasingly demanding applications, an improved procedure for bearing retainer design has been introduced. This paper discusses a methodology which allows the designer to predict the life and failure modes of a retainer under application conditions. Specific attention is given to the case of fatigue of the retainer due to the dynamic interactions between the retainer, rolling elements and races. The methodology which has been developed for the life prediction of retainers is based on the dynamic loads and retainer structural integrity. Central to this technique is the ability to predict the loads imposed on the retainer as a function of design and application conditions. The bearing analysis code ADORE has been used for this purpose. The technique will be discussed by means of an example.

An experimental methodology is proposed to measure the rollover propensity of road tankers when subjected to lateral perturbations derived from steering manoeuvers. The testing principle involves subjecting a scaled down sprung tank to the elimination of a lateral acceleration, to analyze its rollover propensity as a function of various vehicle's operational and design parameters. Initial acceleration is generated through putting the scaled tank on a tilt table supported by a hydraulic piston. The controlled release of the fluid in the hydraulic system generates a perturbation situation for the tank, similar to the one that a vehicle experiences when leaving a curved section of the road and going to a straight segment. Durations for the maneuver and initial tilt angles characterize both the corresponding intensities of the steering maneuver.

Harvesting is one of the most critical operations in grain production. Any means to increase the productivity and efficiency of the agricultural combine harvester has immediate benefits for the producer. This paper reports on an investigation of a control system to automatically and continuously adjust three main parameters, namely, feedrate, sieve airflow and cylinder speed. Results of field testing are presented.

Conventional accumulator charging valves operate automatically and reliably in constant flow industrial hydraulic systems. By contrast, these valves do not necessarily perform reliably in variable flow mobile hydraulic systems because the accumulator circuit charging pump flow changes with the engine speed. Occasionally, the valve sticks in a transitional condition which neither allows the accumulator to fully charge nor lets the charge pump unload. This paper describes the operation of conventional and mobile type accumulator charging valves and describes how the spool design pilot circuit valve improves the reliability of the mobile machine accumulator charging valve.

With India achieving the BSVI milestone, the diesel particulate filter (DPF) has become an imperative component of a modern diesel engine. A DPF system is a device designed to trap soot from exhaust gas of the diesel engine and demands periodic regeneration events to oxidize the accumulated soot particles. The regeneration event is triggered either based on the soot mass limit of the filter or the delta pressure across it. For a Heavy Duty Diesel Engine (HDDE), pressure difference across the DPF is not usually reliable as the size of the DPF is large enough compared to the DPF used ina passenger vehicle diesel engine. Also, the pressure difference across DPF is a function of exhaust mass flow and thus it makes it difficult to make an accurate call for active regeneration. This demands for a very accurate soot estimation model and it plays a vital role in a successful regeneration event.

Overloading of trucks can easily cause damage to roads, bridges and other transportation facilities, and accelerate the fatigue loss of the vehicles themselves, and accidents are prone to occur under overload conditions. In recent years, various countries have formulated a series of management methods and governance measures for truck overloading. However, the detection method for overload behavior is not efficient and accurate enough. At present, the method of dynamic load identification is not perfect. No matter whether it is the dynamic weight measurement method of reconstructing the road surface or the non-contact dynamic weight measurement method, little attention is paid to the difference of different vehicles. Especially for different vehicles, there should be different load limits, and the current devices are not smart enough.