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This research attempts to investigate the effect of change in system curve on the energy intensity method of measurement and verification of energy savings. With recent push from US government on energy efficiency through EPACT 2007 and upturn in performance contracted energy efficiency project implementations the effective and accurate evaluation of energy savings as compared to the baseline is of paramount importance. The authors have studied different methods of Measurement and Verification (M&V) of energy savings from literature to compare and contrast and clearly bring out merits and de-merits of each. Finally, the role of production level variable plays in establishing the baseline energy usage is discussed. Though modern models proposed in the literature of determining baseline energy usage consider production level, this variable is compounded from two variables viz., time of usage of a system and fraction of total capacity usage.

The new General Motors 2-mode hybrid transmission for front-wheel-drive vehicles has been incorporated into a 2009 Saturn Vue by the West Virginia University EcoCAR team. The 2-mode hybrid transmission can operate in either one of two electrically variable transmission modes or four fixed gear modes although only the electrically variable modes were explored in this paper. Other major power train components include a GM 1.3L SDE turbo diesel engine fueled with B20 biodiesel and an A123 Systems 12.9 kWh lithium-ion battery system. Two additional vehicle controllers were integrated for tailpipe emission control, CAN message integration, and power train hybridization control. Control laws for producing maximum fuel efficiency were implemented and include such features as engine auto-stop, regenerative braking and optimized engine operation. The engine operating range is confined to a high efficiency area that improves the overall combined engine and electric motor efficiency.

West Virginia University (WVU) is a participant in EcoCAR - The NeXt Challenge, an Advanced Vehicle Technology Competition sponsored by the U.S. Department of Energy, and General Motors Corporation. During the first year of the competition, the goal of the WVU EcoEvolution Team was to design a novel hybrid-electric powertrain for a 2009 Saturn Vue to increase pump-to-wheels fuel economy, reduce criteria tailpipe emissions and well-to-wheels greenhouse gas emissions (GHG) while maintaining or improving performance and utility. To this end, WVU designed a 2-Mode split-parallel diesel-electric hybrid system. Key elements of the hybrid powertrain include a General Motors 1.3L SDE Turbo Diesel engine, a General Motors Corporation 2-Mode electrically variable transmission (EVT) and an A123 Systems Lithium-Ion battery system. The engine will be fueled on a blend of 20% soy-derived biodiesel and 80% petroleum-derived ultra-low sulfur diesel fuel (B20).

The emissions reduction of Fischer-Tropsch (FT) diesel fuel has been demonstrated in several recent publications in both laboratory engine testing and in-use vehicle testing. Reduced emission levels have been attributed to several chemical and physical characteristics of the FT fuels including reduced density, ultra-low sulfur levels, low aromatic content and high cetane rating. Some of the effects of these attributes on the combustion characteristics in diesel engines have only recently been documented. In this study, a Ricardo Proteous, single-cylinder, 4-stroke DI engine is instrumented for in-cylinder pressure measurements. The engine was run at several steady engine states at multiple timing conditions using both federal low sulfur and natural gas derived FT fuels. The emissions and performance data for each fuel at each steady state operating conditions were compared.

Automotive industries in the US and around the world have enormous impact on the economy of each country. Not just the major vehicle manufacturer, but all the other companies in the supply chain are equally important. This was evident with the earthquake and Tsunami that happened in March 2011. Because of the massive destruction at suppliers' facilities, the automakers in the US and other countries struggled to get the necessary parts and supplies. This created a ripple effect throughout the world and led to the closure of several automakers' facilities for a long time. Thus, the automotive supply chains are as important as the main automotive manufacturing facilities. Since these suppliers produce a lot of parts and supplies, the corresponding energy usage is also significant. The current research is focused on compressed air and process heating system analysis at one of the automotive parts manufacturer in Mexico.

The federal emission standards for heavy duty vehicle engines require the exhaust emissions to be measured and calculated in unit form as grams per break horse-power-hour (g/bhp-hr). Correct emission results not only depend on the precise emission measurement but also rely on the correct determination of vehicle energy consumption. A Transportable Heavy-Duty Vehicle Emission Testing Laboratory (THDVETL) designed and constructed at West Virginia University provides accurate vehicle emissions measurements in grams over a test cycle. This paper contributes a method for measuring the energy consumption (bhp-hr) over the test cycle by a chassis dynamometer. Comparisons of analytical and experimental results show that an acceptable agreement is reached and that the THDVETL provides accurate responses as the vehicle is operated under transient loads and speeds. This testing laboratory will have particular value in comparing the behavior of vehicles operating on alternative fuels.

A set of experiments were conducted to evaluate the performance differences between a Low Heat Rejection Engine (LHRE) which is ceramic-insulated and a conventional baseline metal diesel engine which is water-cooled. Both engines were single cylinder, direct injection, and turbocharged. The objective of the study was to investigate the rate of heat release of these engines so that performance improvement procedures could be obtained. In this paper, the difference of the ignition delay between the two engines was determined. Two methods for improving the combustion process of the LHRE were studied: use of mixture fuels and increase the fuel injection rate. Both methods proved effective and reduced the fuel consumption rate of the LHRE.

A bi-fuel engine with the ability to run optimally on both compressed natural gas (CNG) and gasoline is being developed. Such bi-fuel automotive engines are necessary to bridge the gap between gasoline and natural gas as an alternative fuel while natural gas fueling stations are not yet common enough to make a dedicated natural gas vehicle practical. As an example of modern progressive engine design, a Saturn 1.9 liter 4-cylinder dual overhead cam (DOHC) engine has been selected as a base powerplant for this development. Many previous natural gas conversions have made compromises in engine control strategies, including mapped open-loop methods, or resorting to translating the signals to or from the original controller. The engine control system described here, however, employs adaptive closed-loop control, optimizing fuel delivery and spark timing for both fuels.

The need to assess the effect of exhaust gas emissions from heavy duty vehicles (buses and trucks) on emission inventories is urgent. Exhaust gas emissions measured during the fuel economy measurement test procedures that are used in different countries sometimes do not represent the in-use vehicle emissions. Since both local and imported vehicles are running on the roads, it is thought that studying the testing cycles of the major vehicle manufacturer countries is worthy. Standard vehicle testing cycles on chassis dynamometer from the United States, Canada, European Community Market, and Japan1 are considered in this study. Each of the tested cycles is categorized as either actual or synthesized cycle and its representativness of the observed driving patterns is investigated. A total of fourteen parameters are chosen to characterize any given driving cycle and the cycles under investigation were compared using these parameters.

In this paper, a new method for the hydro-dynamic analysis of a sliding cylinder in a fully lubricated parallel track is presented. The method is an extension of Booker's “Mobility Method” (developed for cylindrical journal bearings) to the case of sliding cylinders, in which the clearance between the track and the cylinder, the viscosity of the lubricant, the radius and length of the pin, the sliding velocity and the applied transverse load determine the hydrodynamic behavior of the cylinder. In the Rand Cam™ Engine [1]*, the axicycloidal motion of vanes is driven by a rotor and a cylindrical cam, and one of the alternative designs to provide this function is based on a cylindrical pin sliding within a track which follows the profile of the motion of the main cams of the engine. This function is very important for the engine, since it separates the load bearing function from the sealing function left to the apex-like seals.

A novel engine concept, currently under study, addresses many of the problems commonly associated with conventional internal combustion engines. In its simplest form the novel engine consists of a single crankshaft operating both a piston compressor and a piston expander which are connected by a continuous flame combustion chamber. One might regard this as a Brayton piston engine which is similar to a previous engine investigated by Warren. Also, due to the use of piston cylinders as the compression and expansion devices, this engine varies little mechanically from current engine technology thus allowing for easy implementation. The main improvement from conventional engine design is that the expansion cylinder can have a larger displacement than that of the compression cylinder. This allows more power to be extracted by lowering the loss due to blowdown and this will increase the thermal efficiency.

The Stiller-Smith mechanism is a new mechanism for the translation of linear motion into rotary motion, and has been considered as an alternative to the conventional slider-crank mechanism in the design of internal combustion engines and piston compressors. Piston motion differs between the two mechanisms, being perfectly sinusoidal for the Stiller-Smith case. Plots of dimensionless volume and volume rate-change are presented for one engine cycle. It is argued that the different motion is important when considering rate-based processes such as heat transfer to a cylinder wall and chemical kinetics during combustion. This paper also addresses the fact that a Stiller-Smith engine will be easier to configure for adiabatic operation, with many attendant benefits.

Specific aspects of a study aimed at developing a microwave assisted regeneration system for diesel particulate traps are discussed. Results from thermal and microwave characteristic studies carried out in the initial phase of the study are reported. The critical parameters that need to be optimized, for achieving controlled regeneration, are microwave preheating time period, regenerative air supply, regenerative air temperature, and soot deposition. Using a 1000 W magnetron, power measurements were made to select the best waveguide configuration for optimized transmission. A six cylinder naturally aspirated, indirect injection diesel engine was retrofitted with a customized exhaust system that included a Corning EX80 (5.66″ × 6.00″) type ceramic particulate trap. An automated exhaust bypass system enabled trap loading and subsequent regeneration with a customized microwave regeneration system. The paper discusses the salient details of both on-line and off-line regeneration setups.

Speed-time and video data were logged for tractor-trailers performing local deliveries in Akron, OH. and Richmond, VA. in order to develop an emissions test schedule that represented real truck use. The data bank developed using these logging techniques was used to create a Yard cycle, a Freeway cycle and a City-Suburban cycle by the concatenation of microtrips. The City-Suburban driving cycle was converted to a driving route, in which the truck under test would perform at maximum acceleration during certain portions of the test schedule. This new route was used to characterize the emissions of a 1982 Ford tractor with a Cummins 14 liter, 350 hp engine and a 1998 International tractor with a Cummins 14 liter, 435 hp engine. Emissions levels were found to be repeatable with one driver and the driver-to-driver variation of NOx was under 4%, although the driver-to-driver variations of CO and PM were higher.

Hybrid-electric transit buses offer benefits over conventional transit buses of comparable capacity. These benefits include reduced fuel consumption, reduced emissions and the utilization of smaller engines. Factors allowing for these benefits are the use of regenerative braking and reductions in engine transient operation through sophisticated power management systems. However, characterization of emissions from these buses represents new territory: the whole vehicle must be tested to estimate real world tailpipe emissions levels and fuel economy. The West Virginia University Transportable Heavy Duty Emissions Testing Laboratories were used to characterize emissions from diesel hybrid-electric powered as well as diesel and natural gas powered transit buses in Boston, MA and New York City.

West Virginia University characterized the emissions and fuel economy performance of a 30-foot 2010 transit bus equipped with urea selective catalytic reduction (u-SCR) exhaust aftertreatment. The bus was exercised over speed-time driving schedules representative of both urban and on-highway activity using a chassis dynamometer while the exhaust was routed to a full-scale dilution tunnel with research grade emissions analyzers. The Paris speed-time driving schedule was used to represent slow urban transit bus activity while the Cruise driving schedule was used to represent on-highway activity. Vehicle weights representative of both one-half and empty passenger loading were evaluated. Fuel economy observed during testing with the urban driving schedule was significantly lower (55%) than testing performed with the on-highway driving schedule.

Racing continues to be the singular, preeminent source of powertrain development for automakers worldwide. Engineering teams rely on motorsports for the latest prototype testing and research. Endurance racing provides the harshest and most illuminating stage for system design validation of any motorsport competition. While advancements throughout the 20th Century brought about dramatic increases in engine power output, the latest developments from endurance racing may be more impactful for fuel efficiency improvements. Hybrid powertrains are a critical area of research for automakers and are being tested on the toughest of scales. Prototype Powertrain in Motorsport Endurance Racing brings together ten vital SAE technical papers and SAE Automotive Engineering magazine articles surrounding the advancements of hybrid powertrains in motorsports.