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Recently conducted work has been funded by the California Air Resources Board (CARB) to explore the feasibility of achieving 0.02 g/bhp-hr NOX emissions for heavy-duty on-road engines. In addition to NOX emissions, greenhouse gas (GHG), CO2 and methane emissions regulations from heavy-duty engines are also becoming more stringent. To achieve low cold-start NOX and methane emissions, the exhaust aftertreatment must be brought up to temperature quickly while keeping proper air-fuel ratio control; however, a balance between catalyst light-off and fuel penalty must be addressed to meet future CO2 emissions regulations. This paper details the work executed to improve catalyst light-off for a natural gas engine with a close-coupled and an underfloor three-way-catalyst while meeting an FTP NOX emission target of 0.02 g/bhp-hr and minimizing any fuel penalty.

The Rotating Liner Engine (RLE) is an engine design concept where the cylinder liner rotates in order to reduce piston assembly friction and liner/ring wear. The reduction is achieved by the elimination of the mixed and boundary lubrication regimes that occur near TDC. Prior engines for aircraft developed during WW2 with partly rotating liners (Sleeve Valve Engines or SVE) have exhibited reduction of bore wear by factor of 10 for high BMEP operation, which supports the elimination of mixed lubrication near the TDC area via liner rotation. Our prior research on rotating liner engines experimentally proved that the boundary/mixed components near TDC are indeed eliminated, and a high friction reduction was quantified compared to a baseline engine. The added friction required to rotate the liner is hydrodynamic via a modest sliding speed, and is thus much smaller than the mixed and boundary friction that is eliminated.

To perform coastdown tests on heavy-duty trucks, both long acceleration and coasting distances are required. It is very difficult to find long flat stretches of road to conduct these tests; for a Class 8 truck loaded to 80,000 lb, about 7 miles of road is needed to complete the coastdown tests. In the present study, a method for obtaining coastdown coefficients from data taken on a road of variable grade is presented. To this end, a computer code was written to provide a fast solution for the coastdown coefficients. Class 7 and Class 8 trucks were tested with three different weight configurations: empty, “cubed-out” (fully loaded but with a payload of moderate density), and “weighed-out” (loaded to the maximum permissible weight).

EmiSense Technologies, LLC (www.emisense.com) is commercializing its electronic particulate matter (PM) sensor that is based on technology developed at the University of Texas at Austin (UT). To demonstrate the capability of this sensor for real-time PM measurements and on board diagnostics (OBD) for failure detection of diesel particle filters (DPF), independent measurements were performed to characterize the engine PM emissions and to compare with the PM sensor response. Computational fluid dynamics (CFD) modeling was performed to characterize the hydrodynamics of the sensor's housing and to develop an improved PM sensor housing with reproducible hydrodynamics and an internal baffle to minimize orientation effects. PM sensors with the improved housing were evaluated in the truck exhaust of a heavy duty (HD) diesel engine tested on-road and on a chassis dynamometer at the University of California, Riverside (UCR) using their Mobile Emissions Laboratory (MEL).

The Texas Department of Transportation (TxDOT) began using an emulsified diesel fuel as an emissions control measure in July 2002. They initiated a study of the effectiveness of this fuel in comparison to conventional diesel fuel for TxDOT's Houston District operations and included the fleet operated by the Associated General Contractors (AGC) in the Houston area. Cost-effectiveness analyses, including the incremental cost per ton of NOx removed, were performed. NOx removal was the focus of this study because Houston is an ozone nonattainment area, and NOx is believed to be the limiting factor in ozone formation in the Houston area. The cost factors accounted for in the cost-effectiveness analyses included the incremental cost of the fuel (including an available rebate from the State of Texas), the cost of refueling more often, implementation costs, productivity costs, maintenance costs, and various costs associated with the tendency of the emulsion to separate.

This paper discusses the Formula SAE Student Engineering Design Competition that was held May 24-26, 1984. As was the case of previous student engineering design competitions, the purpose of the Formula SAE Competition is to enhance engineering education by requiring students to apply the technical knowledge gained in their coursework to a practical engineering design problem including choice of appropriate design criteria, design, fabrication, testing, and evaluation. For the Formula SAE Competition, the design problem chosen is to design, construct, and compete a low powered Formula type race car. The purpose of this paper is to describe the 1984 Formula SAE Competition and to present the results of this event. It is expected that this paper will serve as a guide to hosts of similar competitions and will aid future Formula SAE competitors.

This paper discusses the Formula SAE Student Engineering Design Competition that was held May 26-28, 1983. As was the case of previous student engineering design competitions, the purpose of the Formula SAE Competition is to enhance engineering education by requiring students to apply the technical knowledge gained in their coursework to a practical engineering design problem including choice of appropriate design criteria, design, fabrication, testing, and evaluation. For the Formula SAE Competition, the design problem chosen is to design, construct, and compete a low powered Formula type race car. The purpose of this paper is to describe the 1983 Formula SAE Competition and to present the results of this event. It is expected that this paper will serve as a guide to hosts of similar competitions and will aid future Formula SAE competitors.