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Ever increasing price of the fossil fuels, and fast depletion of the petroleum reserves world wide, have greatly encouraged the utilization of the alternative and renewable fuels for the production of electricity and motive power. Among the alternative renewable fuels, landfill gases which were produced by the anaerobic decomposition of organic waste in the landfills and solid waste dump sites were underutilized and overlooked in the past. Lately, there has been an increased interest in this research as the utilization of the landfill gas would provide energy independence, generate revenue and create environmental benefits. They are used both in the internal combustion engines and gas turbines for energy production needs. However because of the low heating value (Btu) content in the landfill gases, competitive energy market and other issues, they were not considered for the energy production in the past in most of the cases.

This paper presents an extension of our earlier work on Cummins Vehicle Mission Simulation (VMS) software. Previously, we presented VMS as a Windows based analysis tool to simulate vehicle missions quickly and to gauge, communicate, and improve the value proposition of Cummins engines to customers. We have subsequently extended this VMS architecture to build a grid-computing platform to support high volume of simulation needs. The building block of the grid-computing version of VMS is an executable file that consists of vehicle and engine simulation models compiled using Real Time Workshop. This executable file integrates MATLAB and Simulink with Java, XML, and JDBC technologies and interacts with the MySQL database. Our grid consists of a cluster of twenty Linux servers with quad-core processors. The Sun Grid Engine software suite that administers this cluster can batch-queue and execute 80 simulations concurrently.

The transportation sector contributes significantly to emissions and air pollution globally. Emission models of modern vehicles are important tools to estimate the impact of technologies or controls on vehicle emission reductions, but developing a simple and high-fidelity model is challenging due to the variety of vehicle classes, driving conditions, driver behaviors, and other physical and operational constraints. Recent literature indicates that neural network-based models may be able to address these concerns due to their high computation speed and high-accuracy of predicted emissions. In this study, we seek to expand upon this initial research by utilizing several deep neural networks (DNN) architectures such as a recurrent neural network (RNN) and a convolutional neural network (CNN). These DNN algorithms are developed specific to the vehicle-out emissions prediction application, and a comprehensive assessment of their performances is done.

Heavy-duty commercial vehicles consume a significant amount of energy due to their large size and mass, directly leading to vehicle operators prioritizing energy efficiency to reduce operational costs and comply with environmental regulations. One tool that can be used for the evaluation of energy efficiency in heavy-duty vehicles is the evaluation of energy efficiency using vehicle modeling and simulation. Simulation provides a path for energy efficiency improvement by allowing rapid experimentation of different vehicle characteristics on fuel consumption without the need for costly physical prototyping. The research presented in this paper focuses on using real-world, sparsely sampled telematics data from a large fleet of heavy-duty vehicles to create high-fidelity models for simulation. Samples in the telematics dataset are collected sporadically, resulting in sparse data with an infrequent and irregular sampling rate.

The measurement of solid particles down to 10 nm is being incorporated into global technical regulations (GTR). This study explores the measurement of solid particles below 23 nm by using both current and proposed particle number (PN) systems having different volatile particle remover (VPR) methodologies and condensation particle counter (CPC) cutoff diameters. The measurements were conducted in dynamometer test cells using ten diesel and eight natural gas (NG) engines that were going under development for a variety of global emission standards. The PN systems measured solid PN from more than 700 test cycles. The results from the preliminary campaign showed a 10-280% increase in PN emissions with the inclusion of particles below 23 nm.

The widely used Chen correlation, consisting of two parts, forced convection and nucleate boiling, was examined with the previously reported experimental data taken in both a flow-loop apparatus and a standard IC engine on subcooled flow boiling for a 50–50 ethylene glycol-water mixture. Comparisons between the Chen correlation and the flow-loop data suggested that a correction factor is required only on the forced convection component of the Chen correlation. The Chen correlation with the correction factor of 2.0 tolerably predicts the heat fluxes and the wall temperatures not only in the flow-loop apparatus but also in the coolant passages of the IC engine.

The development and release process for Cummins first US HD OBD certified product encountered numerous hurdles. Beyond the purely "technical" difficulties, there were also challenges related to our product development processes. This presentation provides recommendations for HD OBD product development processes & improvements. Topics will include: Training needs for program management, Performance tuning strategies vs. OBD needs, Planning for post-certification product changes, etc. Presenter Greg Moore, Cummins Inc.

Although hybrid variants of Automated Mechanical Transmissions such as the Dual Clutch Transmissions are less affected by driveline torque interrupts, actuator dynamics is very critical in the speed of gear pre-selection and during multiple gear shifts. To avoid torque interrupts, such systems require precise gearshift duration hence the actuators are expected to have fast, stable and predictable responses. However, actuator dynamics and controls remain barriers to attaining the full benefits of such complex systems, demanding precise timing and coordination of the gearshifts alongside the clutches engagement and disengagement. To overcome such challenges, a dynamic model of an electro-hydraulic gearshift actuator, the synchronizer and the shift fork has been developed. The model predicts the gearshift actuator dynamics for a given set of input parameters, which can be correlated against experimental data.

In recent years, the focus on engine parasitic losses has increased as a result of the efforts to increase engine efficiency and reduce greenhouse gasses. The engine gear train, used to time the valve system and drive auxiliary loads, contributes to the overall engine parasitic losses. Anti-backlash gears are often used in engine gear trains to reduce gear rattle noise resulting from the torsional excitation of the gear train by the engine output torque. Friction between sliding surfaces at the gear tooth is a major source of power loss in gear trains. The effect of using anti-backlash gears on the gear friction power loss is not well known. As a part of the effort to reduce parasitic losses, the increase in friction power loss in the Cummins ISX 15 gear train due to the anti-backlash gear was quantitatively determined by modifying the methods given in ISO 14179-2 to fit the anti-backlash gear sub-assembly.

Traditionally, most charge air coolers (CACs) have been constructed using the Nocolok aluminum brazing process. The Nocolok process uses flux, some of which remains after the manufacturing process, and migrates through the intake tract to the engine during normal use. This migration and deposition on engine components can cause a variety of issues with engine operation. Currently the only alternative to Nocolok brazed CACs for engines sensitive to flux migration is vacuum brazing, which comes at a significant price increase. In the effort to reduce cost and increase efficiency, there is interest in whether a Nocolok brazed CAC with a reduced amount of flux residue can be successfully applied to flux-sensitive engines.

Good understanding and accurate prediction of component fatigue strength is crucial in the development of modern engine. In this paper a detail analysis was conducted on an engine component made of gray cast iron with finite element method to evaluate the fatigue strength. This component has notches that cause local stress concentration. It is well known that fatigue behavior of a notch is not uniquely defined by the local maximum stress but depends on other factors determined by notch geometry and local stress distribution. The component fatigue strength was underestimated by only considering the stresses on the notch surface for fatigue life prediction. The critical distance approach was adopted to predict the fatigue behavior of this component. Good agreements are observed between predicted life by the critical distance method and actual field data.

Due to increasing expectations for gasoline like sound quality, today's diesel engines for light and medium duty automotive markets needs to be carefully designed from NVH perspective. Typical engine operating conditions such as low idle, light tip in, tip out demand more attention as they are more prone to generating sound quality concerns. Any abrupt change in the noise signature may be perceived as a sign of malfunction and could have a potential to generate warranty claims. In this paper, an experimental investigation was carried out to determine the root cause of the transient oil pressure regulator buzz noise which occurred during no load transients at low engine speeds. The root cause of the objectionable noise was found to be associated with the impacts of the regulator plunger on the valve seat at certain engine speeds. Noise and vibration diagnostic tests confirmed that the plunger impacts at the seat caused the objectionable buzz noise.

In the design of automotive and heavy equipment engines, accurate analysis of factors which influence immediate and long-term effects is essential. Fastener torque, thermal and pressure variations are utilized to evaluate basic sensitivity of the engine to these parameters by measurement of cylinder bore and cylinder head distortions. Holographic interferometry was used to measure the cylinder deformation caused by the applied thermal and mechanical loads. A cast iron V-6 engine was used as the test engine. Influences of bolt torquing, as would occur during initial assembly and/or service were evaluated. Pressure on the cylinder walls was simulated by creating a vacuum in the water jackets of the engine block. The effects of thermal loads were evaluated using a temperature controlled liquid flowing through the water jackets. Incremental steady-state loads were applied to investigate the deformation of the engine at specific points in the operating cycle.

Several makes and models of cars were modified for lean-burn operation using the Turbulent Flow Manifold (TFM), a unique intake manifold that provides improved preparation and distribution of the fuel-air mixture. Operation of the TFM is described, and exhaust emissions and fuel economy data are presented for the various cars. Exhaust port liners and thermal reactors were shown to be effective devices for reducing emissions from the basic lean-burn system. One car equipped with the TFM, port liners, and reactors was operated for 50,000 miles on an EPA-type durability test and had emissions well below the 1975 standards for California. Emissions, fuel economy, and durability data are presented.

Emissions regulations for 2007 will likely require engine manufacturers to use a diesel particulate filter (DPF) to meet particulate matter (PM) emission requirements. With the lower operating temperatures of light-duty diesel engines, some form of catalyst will be required to facilitate oxidation of accumulated soot PM to regenerate the DPF. This catalyst can either be permanently applied to the filter substrate in the manufacturing process, or be continuously delivered via the diesel fuel. In this study we examined the impact of using both forms of catalyst. A recently published study of the fuel-borne catalyst additive MMT [1] (Methylcyclopentadienyl Manganese Tricarbonyl), reviewed the performance of MMT in conjunction with an uncatalyzed DPF [2].

Effects of methyl ester biodiesel fuel blends on NOx emissions are studied experimentally and analytically. A precisely controlled single cylinder diesel engine experiment was conducted to determine the impact of a 20% blend of soy methyl ester biodiesel (B20) on NOx emissions. The data were then used to calibrate KIVA chemical kinetics models which were used to determine how the biodiesel blend affects NOx production during the combustion process. In addition, the impact on the engine control system of the lower specific energy content of biodiesel was determined. Both factors, combustion and controls, must be taken into account when determining the net NOx effect of biodiesel compared to conventional diesel fuel. Because the magnitude and even direction of NOx effect changes with engine load, the NOx effect associated with burning biodiesel blends over a duty cycle depends on the duty cycle average power and fuel cetane number.

Heat rejection, liner temperature, exhaust valve seat temperature, and head gasket temperature data were recorded during a full load torque sweep of a compression ignition engine when fueled by No. 2 diesel and an ethanol/diesel fuel blend containing 10% ethanol by volume. Heat balances were calculated for engine operation at various load-speed combinations. The results of this study indicated that a greater than expected volume of E-diesel was required to operate the compression ignition engine at the same torque-speed compared to No. 2 diesel. More E-diesel fuel was required due to lower brake thermal efficiencies for E-diesel. Other than exhaust seat temperatures, there were no appreciable differences in component temperatures measured throughout the engine or the results of the heat balances calculated for the No. 2 diesel and E-diesel fuels.

Dynamometer (dyno) durability testing plays a significant role in reliability and durability assessment of commercial engines. Frequently, durability test procedures are based on warranty history and corresponding component failure modes. Evolution of engine designs, operating conditions, electronic control features, and diagnostic limits have created challenges to historical-based testing approaches. A physics-based methodology, known as Load Matrix, is described to counteract these challenges. The technique, developed by AVL, is based on damage factor models for subsystem and component failure modes (e.g. fatigue, wear, degradation, deposits) and knowledge of customer duty cycles. By correlating dyno test to field conditions in quantifiable terms, such as customer equivalent miles, more effective and efficient durability test suites and test procedures can be utilized. To this end, application of Load Matrix to a heavy-duty diesel engine is presented.

An existing pass by noise data acquisition system was upgraded to provide the sophisticated data analysis techniques and test site efficiency required to comply with the current and future drive by noise regulations. Use of six sigma tool such as voice of the customer helped in defining the customer requirements which were then translated into the desired engineering characteristics using QFD. Pugh concept matrix narrowed down the best option suitable for the test site modifications taking into account the critical constraints such as test complexity, system cost & transparency to the existing drive by noise setup. Features of the new system include data telemetry, frequency analysis, portability and efficient data management through the use of advanced data acquisition system. Wireless mode of the data transmission helped significantly avoid most of the test site modifications, which in turn helped to reduce the overall system implementation cost.

Additive control of DIG injector coking was investigated on two dynamometer-operated engines and validated in a vehicle. The first engine was a Nissan research “mule” engine designed to severely coke the injectors so that additive effect could be more easily discriminated. Initial additive screening and optimization was carried out in this engine and a few chosen candidates of the Mannich chemistry-type were further optimized in the second engine, and in a vehicle. The second engine, which was also dynamometer operated, was an advanced wall-guided design capable of both homogeneous and stratified operation. On this engine we were able to optimize the Mannich additive “Man C-2” separately in two different carrier systems to show a carrier effect, and by manipulating the purity of the base detergent Man C-2 to show a detergent activity modulation by trace co-products.