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The nonroad Final Tier 4 US EPA emission standards require 88% reduction in NOx emission from the Interim Tier 4 standards. It is necessary to utilize aftertreatment technologies to achieve the required NOx reduction. The development of a fuel reformer, lean NOx trap (LNT) and optional selective catalytic reactor (SCR) on a John Deere 4045 nonroad engine is described in this paper. The paper discusses aftertreatment system performance, catalyst formulations and system controls of a fuel vaporizer, fuel reformer, LNT and SCR system designed to meet the nonroad Final Tier 4 emission standards. The 4045 John Deere engine was calibrated and integrated with the aftertreatment system. The system performance was characterized in an engine dynamometer performance test cell, durability test cell and on a vehicle. The catalyst performance was evaluated using aged catalysts and a detailed description of the LNT, DPF and SCR catalysts is provided.

Architecting and integrating commercial hybrid electric vehicles (HEV) is a long and labor intensive process which is unique every time. The challenge intensifies when one attempts to create an HEV capable of engine-off operation. In this case, electrical power needs to be supplied to devices which are normally powered by the engine accessory belt. These devices are referred to as e-accessories. To address the issue of time to market and reduce vehicle integration burden, a plug-and-play architecture for connecting e-accessories has been developed. The Flexible High Voltage DC System is analogous to a USB hub on a PC and serves to provide power, control and communication to e-accessories such as electrified power steering, electrified brakes and electrified HVAC.

In order to improve power density, the majority of diesel engines have intake manifold pressures above atmospheric conditions. This allows for the introduction of more fuel, which results in more power. Except for a few applications, these engines receive charged air from a turbocharger. The turbocharger develops boost by converting exhaust gas energy into power. This power is then used to compress the intake charge. The medium- and heavy-duty engine markets have both stringent regulatory targets and customer demand for improved fuel efficiency. Two approaches used to meet fuel efficiency targets are downspeeding and downsizing. Until now, the industry has adapted to the turbocharger lag experienced during a transient acceleration event. This performance deficiency is severely exaggerated when the displacement and speed of an engine are reduced. The solution proposed to improving fuel economy, while maintaining equivalent performance, is supercharging.

The lubricant wear and degradation is a major cause of failure in industrial machines such as engines, pumps and gearboxes. This is primarily due to contaminants such as metal debris particles and depletion of the chemical and physical properties. This paper presents a low cost, multi-functional sensor for real-time monitoring of both oil level and the debris particles in oil lubricants for a gearbox application. The sensor system achieves a micrometer-order resolution (37.5 μm), high linearity (< 0.5 mm non-linearity) and insensitivity to viscosity changes due to wide temperature fluctuations from −40 °C to 135 °C, and is designed for ease of manufacturing and application in harsh transmission environment. The synergy from simultaneous data analysis from a multi-functional sensor has been demonstrated both qualitatively and quantitatively using mathematical analysis, computer simulation and physical experiments.

The approach towards building hybrid vehicles has evolved with time and requirements. What used to be direct prototype building activity has moved towards building mathematical models before the actual prototypes are built. These models are utilized in optimizing component sizes, design and calibrate controllers and to estimate fuel economy improvements. If model results show promise, the actual prototype building activity is started. But modeling of vehicles still has a long way to go before aligning with businesses and aiding them as decision making tools on R&D investments. The reason being - the model building activity itself is prolonged and expensive. In addition to this, a lot of proprietary information such as component efficiency maps is required in order to build the model. In absence of these component level data, extensive testing becomes necessary where again vast amounts of resources have to be allocated.

The problem with traditional drive cycle fuel economy analysis is that kinematic (backward looking) models do not account for transient differences in charge air handling systems. Therefore, dynamic (forward looking) 1D performance simulation models were created to predict drive cycle fuel economy which encompass all the transient elements of fully detailed engine and vehicle models. The transient-capable technology of primary interest was mechanical supercharging which has the benefit of improved boost response and "time to torque." The benefits of a supercharger clutch have also been evaluated. The current US class 6-8 commercial vehicle market exclusively uses turbocharged diesel engines. Three vehicles and baseline powertrains were selected based on a high-level review of vehicle sales and the used truck marketplace. Fuel economy over drive cycles was the principal output of the simulation work. All powertrains are based on EPA 2010 emission regulations.

Dual clutch based transmissions (DCT) have been developed for passenger vehicles in Europe. Compared to a single clutch based transmission (SCT), DCT eliminates torque interrupts during gear-shifting so that the vehicles can run as smooth as one using an automatic transmission (AT). Traditionally AT needs to use torque converters to transmit engine torque to drivelines. However, a torque converter is complicated and expensive, and offers lower driveline efficiency than SCT and DCT. DCT technology is a cost-effective avenue to achieve smooth shifting while taking advantage of the some beneficial features of both AT and SCT. This paper presents the results of an analysis of the application of DCT on medium duty (MD) trucks. First, we set up a 6-speed DCT with two groups of three gear ratios in correspondence to two ceramic dry clutches. Clutch dampers are included in the DCT model. For simplicity but without loss of generality, the synchronizers are not included for this study.

Experimental test and theoretical analysis have been used to identify diesel engine valve heat flow in both conventional intake and exhaust valves and in metallic heat barrier intake and exhaust valves. Significant changes in valve surface temperature both on the intake fillet region and on the valve head have been achieved. A quasi-steady state finite element heat transfer analysis has been used to define heat flow by matching experimentally measured temperatures and temperature profiles. Heat flow on the intake valve fillet region has been changed with up to 90 percent blocked. Fifty percent of the heat flow from the combustion chamber side of the valve has been blocked with advance techniques promising 75% blockage.