2024-03-28
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2024-03-28
2024-03-28
Technical Paper
1970s Development of 21st Century Mobile Dispersed Power
1973-02-01
730709
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.
Technical Paper
2-Cycle Methanol LHR Engine and It's Characteristics
1994-10-01
941910
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.
Technical Paper
A 3D-Simulation with Detailed Chemical Kinetics of Combustion and Quenching in an HCCI Engine
2008-06-23
2008-01-1655
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.
Journal Article
A Carbon Intensity Analysis of Hydrogen Fuel Cell Pathways
2021-03-02
2021-01-0047
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.
Technical Paper
A Compact 10 kW Electric Power Range Extender Suitable for Plug-In and Series Hybrid Vehicles
2011-09-11
2011-24-0085
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.
Technical Paper
A Comparative Analysis of Alternative Fuel Infrastructure Requirements
1989-09-01
892065
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.
Technical Paper
A Comparative Study of Methanol-Gasoline Blends on Performance and Emissions on BS-IV and BS-VI Class of Two Wheeler Vehicles
2024-01-16
2024-26-0073
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.
Technical Paper
A Comparative Study on the Effect of Alcohol Induction and Addition on Performance Behavior of a CI Engine Fueled with “Madhuca Indica” as Fuel
2015-04-14
2015-01-0853
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.
Technical Paper
A Comparison Between the Combustion of Isooctane, Methanol, and Methane in Pulse Flame Combustors with Closed Loop A/F Control
1992-02-01
920799
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.
Technical Paper
A Comparison Of Engine Performance Using Methanol Or Dissociated Methanol As The Fuel
1984-01-01
845128
Technical Paper
A Comparison of Engine Oil Viscosity, Emulsion Formation, and Chemical Changes for M85 and Gasoline-Fueled Vehicles in Short-Trip Service
1992-10-01
922297
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).
Technical Paper
A Comparison of Methanol and Dissociated Methanol Illustrating Effects of Fuel Properties on Engine Efficiency—Experiments and Thermodynamic Analyses
1985-02-01
850217
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.
Technical Paper
A Comparison of Methanol, Methane and Hydrogen Fuels for SI Engines: Performance and Pollutant Emissions
2023-08-28
2023-24-0037
The urban mobility electrification has been proposed as the main solution to the vehicle emission issues in the next years. However, internal combustion engines have still great potential to decarbonize the transport sector through the use of low/zero-carbon fuels. Alcohols such us methanol, have long been considered attractive alternative fuels for spark ignition engines. They have properties similar to those of gasoline, are easy to transport and store. Recently, great attention has been devoted to gaseous fuels that can be used in existing engine after minor modification allowing to drastically reduce the pollutant emissions. In this regard, this study tries to provide an overview on the use of alternative fuels, both liquid and gaseous in spark ignition engines, highlighting the benefits as well as the criticalities. The investigation was carried out on a small displacement spark ignition engine capable to operate both in port fuel and direct injection mode.
Technical Paper
A Comparison of Thermal Efficiency of Carbureted and Injection Methanol Engines by Means of Thermodynamic Cycle Simulation
1987-09-01
871673
Thermal efficiency of carbureted and injection engine was compared through thermodynamic cycle simulation. When the compression ratio is the same, the combined control carbureted engine in which the A/F ratio control method is used in the high load range and the throttling method is used in the low load range shows the highest thermal efficiency followed by the injection engine and the throttling carbureted engine. The thermal efficiency of the injection engine is lower than that of combined control carbureted engine because the temperature of gases in cylinder does not rise much due to stratified charge combustion. When the compression ratio of these engines is optimized, the thermal efficiency is the highest for the injection engine followed by the combined control carbureted engine. The thermal efficiency of the combined control carbureted engine is lower than that of the injection engine at high and low loads, but they are in the same level at intermediate loads.
Technical Paper
A Comparison of the Emissions of Polynuclear Aromatic Hydrocarbons from Automobiles Using Gasoline or a Methanol/Gasoline Blend
1981-02-01
810441
Individual polynuclear aromatic hydrocarbons (PAH) were measured in the exhaust gas from gasoline and gasoline/methanol blend fueled vehicles. Driving cycle tests as well as constant speed conditions were used. Exhaust emission samples were collected on filters together with a condenser. Eleven PAHs were quantified by gas chromatography and FID. PAHs in the fuels were also determined. There was no consistent difference in the amount of PAH-emission when the two fuels, gasoline and the gasoline/methanol blend, were compared. The emissions contain specific PAHs that cannot be found in the fuel.
Technical Paper
A Comprehensive Chemical Kinetic Investigation of the Combustion Processes of Lean Mixtures of Methane and Air
1999-10-25
1999-01-3483
The combustion processes of of lean mixtures of methane in air is examined by employing a detailed chemical kinetic scheme consisting of 178 elementary reaction steps with 41 species. The changes with time in the concentrations of the major relevant reactive species are determined from the preignition reactions to the time near equilibrium conditions. The results of such an approach to the combustion process are considered over a wide range of initial temperatures (1000 K - 1600 K) and equivalence ratios (0.2 - 1.2) while the pressure was kept at atmospheric. Calculated results obtained while using this model tend to be in good agreement with the corresponding experimental values of ignition delay. The ignition delay of methane-air mixture correlated by the following empirical expression in which constants A and B are function of the equivalence ratio while Ti is the initial mixture temperature in °K.
Technical Paper
A Computational Investigation of the Effect of Exhaust Gas Recirculation on the Performance of a Dual Fuel Engine
2000-06-19
2000-01-2040
It is well known the dual fuel operation at lower loads suffers from lower thermal efficiency and higher unburned percentages of fuel. The present work includes a computational investigation to predict the effects of Exhaust gas recirculation (EGR) on the operation of an indirect-injection dual fuel (Ricardo-E6) engine by using a detailed chemical kinetic scheme and a quasi-two zone analytical model. The comprehensive chemical kinetic scheme for methane oxidation consisting of 178 elementary reaction steps with 41 species. A quasi-two zone analytical model is based on the effective energy releases of the pilot diesel fuel while using the detailed chemical reaction kinetic scheme for the oxidation of methane. Through the results, it was shown that, the active species such as H, O and OH produced in the high temperature combustion process and found in the exhaust gases are play a significant role in the preignition reactions.