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A mobile and dispersed power system is necessary for an advanced technological-industrial society. Today's petroleum-based system discharges waste products and heat and is growing exponentially. Energy resource commitment has already intersected “ultimate” low-cost petroleum supplies in the United States and will do so for the world before 2000; this portends major changes and cost increases. The twenty-first century system for mobile-dispersed power will reflect the energy source selected to replace petroleum-for example, coal, solar insolation, or uranium. It will incorporate a fuel intermediate such as methanol, ammonia, or hydrogen, and a suitably matched “engine.” The complete change will require more than 25 years because of the magnitude, fragmentation, structural gaps, complexity, and variety of the mobile-dispersed power system.

Methanol fuel was tested in a prototype 2-cycle ceramic heat insulated engine with a swirl chamber. It was found that the 2-cycle ceramic heat insulated engine with a compression ratio of 18:1 could ignite methanol without an auxiliary ignition system and emissions were substantially reduced in the whole load range.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of this base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The intent of this specification is for the procurement of the material listed on the QPL and, therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program shall refer to the Quality Assurance section of this base specification, AMS3961. All material qualification and equivalency data has been archived and is available for review upon request. Contact the CMH-17 Secretariat (www.cmh17.org) for additional information.

The present study deals with the reduction of fluid vibrations by dissipating the kinetic energy in a closed vibrating container partly filled using vertical slotted obstacles. The effect of the barriers on the liquid vibration inside a closed container exposed to a harmonic excitation is numerically studied. A single vertical slotted barrier (SVSB) and multivertical slotted barrier (MVSB) systems are considered for different liquid levels. The 3D liquid domain with the tank and the barrier as boundaries is modelled and solved numerically using ANSYS-CFX software. The reduction in pressures on the walls and the ceiling of the tank due to the influences of the slot size and numbers were evaluated to optimize the size and the numbers of the slots. The numerical approach shows an ability to simulate the nonlinear behavior of the liquid vibration when using vertical slotted barriers (VSB).

A 3D-CFD model with detailed chemical kinetics was developed to investigate the combustion characteristics of HCCI engines, especially those fueled with hydrogen and n-heptane. The effects of changes in some of the key important variables that included compression ratio and chamber surface temperature on the combustion processes were investigated. Particular attention was given, while using a finer 3-D mesh, to the development of combustion within the chamber crevices between the piston top-land and cylinder wall. It is shown that changes in the combustion chamber wall surface temperature values influence greatly the autoignition timing and location of its first occurrence within the chamber. With high chamber wall temperatures, autoignition takes place first at regions near the cylinder wall while with low surface temperatures; autoignition takes place closer to the central region of the mixture charge.

The requirements for diesel and gasoline engines are continuously increasing with respect to emissions, fuel consumption and durability. Besides the engine development process the quality of the production engine itself has to be ensured. This paper discusses alternative philosophies and approaches in terms of the quality management process. Based on a detailed analysis of the required equipment advanced solutions are presented. Modular containerized test cells are described being equipped exactly to the current testing task ready to use in low infrastructure. The testing capacity of the facility can be adjusted to the actual production volume by simply removing or adding modular test cells. Thus, at every facility the testing tasks can be executed successfully and the investment can be kept low.

A hydrogen economy is an increasingly popular solution to lower global carbon dioxide emissions. Previous research has been focused on the economic conditions necessary for hydrogen to be cost competitive, which tends to neglect the effectiveness of greenhouse gas mitigation for the very solutions proposed. The holistic carbon footprint assessment of hydrogen production, distribution, and utilization methods, otherwise known as “well-to-wheels” carbon intensity, is critical to ensure the new hydrogen strategies proposed are effective in reducing global carbon emissions. When looking at these total carbon intensities, however, there is no single clear consensus regarding the pathway forward. When comparing the two fundamental technologies of steam methane reforming and electrolysis, there are different scenarios where either technology has a “greener” outcome.

The paper discusses the concept, specification and overall performance of a 10 kW electric power range extender suitable for electric plug-in and series hybrid vehicles, based on a single cylinder, high speed, four stroke internal combustion engine, tested and developed at Istituto Motori CNR of Italy. This unit has been conceived from the beginning as a compact on board recharging system for the mentioned kind of means, and especially for city cars and small commercial vehicles. The paper starts by defining some characteristics, advantages and drawbacks of an electric city car, followed by the criteria adopted to characterize the nominal power of the range extender. Then, the ratio which leaded to the adoption of a single cylinder internal combustion engine is discussed, followed by an explanation of the main design characteristics of the whole unit.

This paper presents results of an assessment that identifies vehicle technology and fuel distribution system changes and costs associated with providing sufficient alternative fuels to displace one million barrels/day petroleum in the transportation sector in the 1995-2005 timeframe. The paper concludes that the capital cost of developing fuel delivery systems and a sufficient number of vehicles to achieve this displacement will be $22 billion if the alternative fuel is methanol, $36 billion if natural gas, and $288 billion if electricity. The predominant component of these costs is that of the incremental cost of the vehicles.

Engine knock is a major challenge that limits the achievement of higher engine efficiency by increasing the compression ratio of the engine. To address this issue, using a higher octane number fuel can be a potential solution to reduce or eliminate the propensity for knock and so obtain better engine performance. Methanol, a promising alternative fuel, can be produced from conventional and non-conventional energy resources, which can help reduce pollutant emissions. Methanol has a higher octane number than typically gasolines, which makes it a viable option for reducing knock intensity. This study compared the combustion characteristics of gasoline and methanol fuels in an optical spark-ignition engine using multiple spark plugs. The experiment was carried out on a single-cylinder four-stroke optical engine. The researchers used a customized metal liner with four circumferential spark plugs to generate multiple flame kernels inside the combustion chamber.

Methanol, a fuel obtainable through the capture and conversion of Carbon Dioxide (CO2), has garnered attention as a suitable alternative fuel for gasoline. Methanol-gasoline blends, characterized by their high-octane rating, commendable performance, and reduced carbon emissions, present themselves as promising alternative fuels for internal combustion engines. In the present study, a comprehensive comparative analysis was conducted to assess the performance and emissions characteristics of unmodified vehicles utilizing methanol blends at lower concentrations, ranging up to 30%, in gasoline. The research focused on two distinct classes of vehicles commonly found on the roads of India: those compliant with BS-IV (Euro IV) and BS-VI (Euro VI) emission standards. Experimental evaluations were carried out on a chassis dynamometer, with the vehicles subjected to the Worldwide Harmonized Motorcycle Test Cycle (WMTC) and Wide open throttle (WOT) driving tests.

The effect of methanol addition (by blending) and methanol induction (by carburetion) on performance of a vegetable oil (Madhuca Indica called as Mahua oil) based diesel engine was studied experimentally. A single cylinder, water cooled, DI, diesel engine was used. Baseline data was generated with neat diesel and neat Mahua oil as fuels. Subsequently methanol was blended with Mahua oil in different proportions such as 5, 10, 15 and 20% by mass and tested for engine's performance. Finally the engine was operated in dual fuel mode of operation with methanol induction and Mahua oil injection. Engine performance, emission and combustion characteristics of ND (neat diesel), NMO (neat Mahua oil), MOMB (Mahua oil+15% methanol blend by mass) and MOMDFE (Mahua oil dual fuel engine at 15% mass share) were compared and analyzed at 100% and 40% loads. NMO resulted in inferior performance and increased emissions at both power outputs as compared to ND.

CO/H2 (ratios i.e. water gas shift equilibria) in exhaust gases produced from the combustion of pure isooctane, methanol, and methane in a pulse flame combustor were measured. Measured CO/H2 ratios were directionally consistent with C/H ratios of the respective fuels. The average CO/H2 ratios in combusted isooctane, methanol, and methane were found to be 3.8, 1.25, and 2.0, respectively. The effect of these differences on feedback A/F control with a HEGO (heated exhaust gas oxygen) sensor were also examined. Feedback control of isooctane combustion produced operation very near to stoichiometry. On the other hand, the combustion of methanol under feedback control resulted in steady state lean operation while feedback control of methane combustion produced rich operation. For all three fuels, operation shifted in the lean direction as combustion efficiency was degraded.

Accumulation of fuel, water, acids, insolubles, and metals in engine oil is documented and compared for variable-fueled (fuel containing up to 85 percent methanol) and gasoline-fueled vehicles in short-trip service. The oil temperature at which various contaminants are removed is noted. As a consequence of emulsion formation, the viscosity of the oil in the M85-fueled vehicles increased. Due to the presence of gasoline, the viscosity of the oil in the gasoline-fueled vehicles decreased. Equations were developed to explain both the viscosity reduction due to gasoline and the viscosity increase due to emulsion-forming contaminants (water and methanol).

Methanol, a popular alternative fuel candidate, can theoretically be dissociated on-board a vehicle into a 2/1 molar mixture of hydrogen (H2) and carbon monoxide (CO) having a 14 percent greater heating value than that of methanol vapor. In this study, engine efficiency and fuel consumption with methanol vapor and dissociated methanol (simulated by a 2/1 mixture of Ha and CO) were compared in a single-cylinder engine at equivalence ratios (Φ’s) ranging from 0.5 to 0.9 and compression ratios (CR’s) from 11 to 14. Whan compared at the same Φ and CR, the reduction in fuel consumption for dissociated methanol compared to methanol (3-7 percent) was smaller than would be expected based on heating value alone. Indicated thermal efficiency with dissociated methanol was only 0.89-0.55 times that with methanol. Thermodynamic analyses were conducted to isolate the factors responsible for lower efficiency with dissociated methanol.