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Rankine powerplant advantages are found to fit best applications that call for long maintenance free life, or where the heat energy is essentially free as in bottoming and topping cycles, or in special environments as undersea or space. Worthy applications suggested on the basis of potential market size and ability to satisfy customer imposed cost and performance are: automotive and tank accessory power systems (APS), transportable refrigeration, portable power supply (GPS), standby power, remote site power, and home air conditioner drive. The automotive APS and a 1 1/2 kWe GPS are further analyzed. The APS can offer attractive features to the automobile user, including the possibility of reducing pollution from spark ignition engine. The GPS is an example showing high cost effectiveness for long operating times. It is recommended that marketing and cost studies continue, and that working fluid and heat exchanger technologies be accentuated.

Traditionally, the controls system in production vehicles with automatic transmission interprets the driver’s accelerator pedal position as a demand for transmission input torque. However, with the advent of electrified vehicles, where actuators are located at different positions in the drivetrain, and of autonomous vehicles, which are self-driving, it is more convenient to interpret the demand (either human or virtual) in vehicle acceleration or wheel torque domain. To this end, a Wheel Torque-based longitudinal Control (WTC) framework was developed, wherein demands can be converted accurately between the vehicle acceleration or wheel torque domain and the transmission assembly input torque domain.

The automakers pursue for fuel economy is increasing year after year, both by the demands of society and by political pressures, leading companies to develop new solutions and technologies in order to increase the energy efficiency of vehicles. With the advent of CFD software, it is possible to study drag reduction proposals, which contributes to increase fuel economy. In this context, based on a small sedan vehicle virtual drag model, correlated with the wind tunnel test, a conceptual wheel was assembled proposing 3 blade angles in order to verify the influence on the drag coefficient. Considering the drag contribution of wheel in total vehicle drag is around 25%, this work aims to show the sensitivity in the drag coefficient by changing the wheel rim of a small sedan vehicle.

The word hybrid has been synonymous with higher fuel economy. However, the standard measures of fuel economy in miles per gallon or fuel consumption in liters per 100 km are not able to describe whether any increase in fuel economy is due to the hybrid powertrain or due to other factors such as non-powertrain vehicle modifications. It would be beneficial to have a simple way to describe where the fuel economy benefit is coming from, either from vehicle related enhancements (non-powertrain) or powertrain related enhancements. In this paper, the simplified metrics of Vehicle Limited Fuel Consumption (VLFC) and Powertrain and Braking Efficiency (PABE) are developed. The metrics are then used to characterize hybrid and non-hybrid vehicles and deconvolve the contribution of hybrid and non-hybrid enhancements to vehicle fuel consumption. These metrics can be helpful for communicating to non-experts when examining cost/benefit ratios of potential actions to reduce fuel consumption.

The lack of clearly identified constraints for ignition and flame propagation has hindered understanding the processes which limit lean operation in spark ignition engines. This experimental study explores flame initiation and flame propagation as limits of lean operation in engines. In separate tests conducted in a single-cylinder CFR (cooperative fuel research) engine, the spark timing was either advanced or retarded from MBT* in order to determine the ignition-limit or partial-burn-limit spark timings, respectively. These two limiting spark timings were found to converge at lean mixtures. At the MBT lean misfire limit, the ignition-limit, and the partial-burn-limit spark timing lines converged. Apparently flame initiation as well as flame propagation considerations constrain lean operation. The effects of engine and ignition system-related variables on the ignition and partial-burn limits are presented and discussed.

The potential peaking of world conventional oil production and the possible imperative to reduce carbon emissions will put great pressure on vehicle manufacturers to produce more efficient vehicles, on vehicle buyers to seek them out in the marketplace, and on energy suppliers to develop new fuels and delivery systems. Four cases for stabilizing or reducing light vehicle fuel use, oil use, and/or carbon emissions over the next 50 years are presented. Case 1 - Improve mpg so that the fuel use in 2020 is stabilized for the next 30 years. Case 2 - Improve mpg so that by 2030 the fuel use is reduced to the 2000 level and is reduced further in subsequent years. Case 3 - Case 1 plus 50% ethanol use and 50% low-carbon fuel cell vehicles by 2050. Case 4 - Case 2 plus 50% ethanol use and 50% low-carbon fuel cell vehicles by 2050. The mpg targets for new cars and light trucks require that significant advances be made in developing cost-effective and very efficient vehicle technologies.

The question of whether increasing the fuel economy of light-duty natural gas fueled vehicles can improve their economic competitiveness in the U.S. market, and help the US Department of Energy meet stated goals for such vehicles is explored. Key trade-offs concerning costs, exhaust emissions and other issues are presented for a number of possible advanced engine designs. Projections of fuel economy improvements for a wide range of lean-burn engine technologies have been developed. It appears that compression ignition technologies can give the best potential fuel economy, but are less competitive for light-duty vehicles due to high engine cost. Lean-burn spark ignition technologies are more applicable to light-duty vehicles due to lower overall cost. Meeting Ultra-Low Emission Vehicle standards with efficient lean-burn natural gas engines is a key challenge.

Commuter/regional airlines profits depend largely upon equipment which helps increase revenue a/o minimize operating costs, with former seen more critical. Airframe/component reliability is priority requirement. Maintenance schedules, a/c performance and pax appeal must mesh with demands of high weekday/daytime cycles between congested hubs and rural airports. Manufacturers help regionals most with a/c optimizing a blend of: payload, pressurized pax comfort, ops flexibility and fuel efficiency, progressive/simplified maintenance, airframe/component durability and reliability, low parts count, QC cabin for cargo/charter off-peak opportunities.

Three industrial engines, including one engine at three compression ratios, were operated on LP-gas mixtures and on gasoline. The work was performed by Ethyl Corp. Research Laboratories under contract with the Natural Gas Processors Association and the National LP-Gas Association. The paper presents directly comparable information on engine performance and fuel economy when operated on gasoline and LP-gas. Information is presented to indicate the LP-gas antiknock quality needed to satisfy the engines at best-power fuel-air ratio and various ignition timings.

The turbocharged engine, by operating at intake and discharge conditions several times higher than atmospheric pressure, is capable of increasing its specific output to several times that of its naturally aspirated version, and at better fuel economy. Successful integration of the turbocharger requires recognition of the interrelation and interaction of both reciprocating and turbo machines and changes in their performance characteristics. This paper discusses the relation of intake manifold pressure to engine load and speed as a function of turbocharger performance, and methods of improving performance of the engine at part speed without excessive overboosting at rated speed.

The physical and chemical properties of a mineral-based (Fluid-M) and a partial-synthetic-based (Fluid-PS) automatic transmission fluid were compared by the analyses of Gel Permeation Chromatography (GPC), Thermogravimetry (TG), Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Gas Chromatography (GC), viscometry, thermo-oxidative stability, torque response curve shape and metal-to-metal wear preventive characteristics. The effects of various properties of Fluid-M and Fluid-PS on wet friction material performance were investigated from the viewpoints of compressibility, durability, tensile strength, surface interactions and friction-pressure-speed-temperature characteristics. Friction material specifications for partial-synthetic fluid applications will be different from those for mineral-based fluid applications. GPC showed that Fluid-PS has a higher concentration and a lower molecular weight of VI Improver than Fluid-M.

A fuel-cycle model-called the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model-has been developed at Argonne National Laboratory to evaluate well-to-wheels (WTW) energy and emission impacts of motor vehicle technologies fueled with various transportation fuels. The new GREET version has up-to-date information regarding energy use and emissions for fuel production activities and vehicle operations. In this study, a complete WTW evaluation targeting energy use, greenhouse gases (CO2, CH4, and N2O), and typical criteria air pollutants (VOC, NOX, and PM10) includes the following fuel options-gasoline, diesel, and hydrogen; and the following vehicle technologies-spark-ignition engines with or without hybrid configurations, compression-ignition engines with hybrid configurations, and hydrogen fuel cells with hybrid configurations.

Gasoline Compression Ignition (GCI) engines using a low octane gasoline-like fuel (LOF) have good potential to achieve lower NOx and lower particulate matter emissions with higher fuel efficiency compared to the modern diesel compression ignition (CI) engines. In this work, we conduct a well-to-wheels (WTW) analysis of the greenhouse gas (GHG) emissions and energy use of the potential LOF GCI vehicle technology. A detailed linear programming (LP) model of the US Petroleum Administration for Defense District Region (PADD) III refinery system - which produces more than 50% of the US refined products - is modified to simulate the production of the LOF in petroleum refineries and provide product-specific energy efficiencies. Results show that the introduction of the LOF production in refineries reduces the throughput of the catalytic reforming unit and thus increases the refinery profit margins.

The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model incorporated fuel economy and electricity use of alternative fuel/vehicle systems simulated by the Powertrain System Analysis Toolkit (PSAT) to conduct a well-to-wheels (WTW) analysis of energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). Based on PSAT simulations of the blended charge depleting (CD) operation, grid electricity accounted for a share of the vehicle’s total energy use ranging from 6% for PHEV 10 to 24% for PHEV 40 based on CD vehicle mile traveled (VMT) shares of 23% and 63%, respectively. Besides fuel economy of PHEVs and type of on-board fuel, the type of electricity generation mix impacted the WTW results of PHEVs, especially GHG emissions.

The automotive industry is facing a major challenge to incorporate additional powertrain function into smaller more complex packages to meet mandated fuel economy standards and ever increasing world wide competition. An important tool available to meet these challenges is the use of latest Welded Steel Tube technology to develop new concepts for manufacture of the more complex automatic transmission races, gears, hubs and shafts of the future. Advantages of Welded Steel Tubing over seamless tubing, forgings and castings include: Closer raw material tolerances which significantly reduce material waste. Higher productivity, lower tool cost and reduced scrap resulting from lighter machining cuts and/or elimination of entire machining operations. Complex part shape cold formability directly from commercially available material without the need for prior truing operations. Stronger more durable components.

Welding has been used extensively in automotive components design due to its flexibility to be applied in manufacturing, high structural strength and low cost. To improve fuel economy and reduce material cost, weight reduction by optimized structural design has been a high priority in auto industry. In the majority of heavy duty vehicle's chassis components design, the ability to predict the mechanical performance of welded joints is the key to success of structural optimization. FEA (finite element analysis) has been used in the industry to analyze welded parts. However, mesh sensitivity and material properties have been major issues due to geometry irregularity, metallurgical degradation of the base material, and inherent residual stress associated with welded joints. An approach, equilibrium-equivalent structural stress method, led by Battelle and through several joint industrial projects (JIP), has been developed.

Due to the contradiction of the market demands and legal issues OEMs are forced to invest in finding concepts that assure high fuel economy, low exhaust emissions and high specific power at the same time. Since mechanical losses may amount up to 10 % of the fuel energy, a key to realise such customer/government specific demands is the improvement of the mechanical performance of the engines, which comprises mainly friction decrease and lightweight design of the engine parts. In order to achieve the mentioned objectives, it has to be checked carefully for each component whether the design potentials are utilized. Many experimental studies show that there is still room for optimization of the cranktrain parts, especially for the crankshaft. A total exploitation of the crankshaft potentials is only possible with advanced calculation approaches that ensure the component layout within design limits.

EcoCAR 3 is a university based competition with the goal of hybridizing a 2016 Chevrolet Camaro to increase fuel economy, decrease environmental impact, and maintain user acceptability. To achieve this goal, university teams across North America must design, test, and implement automotive systems. The Colorado State University (CSU) team has designed a parallel pretransmission plug in hybrid electric design. This design will add torque from the engine and motor onto a single shaft to drive the vehicle. Since both the torque generating devices are pre-transmission the torque will be multiplied by both the transmission and final drive. To handle the large amount of torque generated by the entire powertrain system the vehicle's rear half-shafts require a more robust design. Taking advantage of this, the CSU team has decided to pursue the use of composites to increase the shaft's robustness while decreasing component weight.

In order to improve the fuel economy of automobiles, further increase in the efficiency of gasoline engines is strongly demanded. In particular, reducing the weight of the pistons plays a major role. The pistons in this engine were connected to the connecting rods by a spherical joint bearing instead of a conventional piston pin, and a thin-walled piston top with radial rib structure was employed to reduce the piston weight. To ensure the required piston functions, lubrication of the bearing, cooling of piston top and the skirt design for smooth motion were important challenges to realize weight reduction of the spherical joint piston. In this paper, firstly, the lubrication characteristics of the ball were evaluated using a high frequency fluctuating load device to minimize the diameter of the ball of the spherical bearing. In the next step, cooling of the thin-walled piston top structure by oil fed through the connecting rod was investigated.