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The development of PM and NOx reduction system with the combination of DOC included DPF and SCR catalyst in addition to the AOC sub-assembly for NH3 slip protection is described. DPF regeneration strategy and manual regeneration functionality are introduced with using ITH, HCI device on the EUI based EGR, VGT 12.3L diesel engine at the CVS full dilution tunnel test bench. With this system, PM and NOx emission regulation for JPNL was satisfied and DPF regeneration process under steady state condition and transient condition (JE05 mode) were successfully fulfilled. Manual regeneration process was also confirmed and HCI control strategy was validated against the heat loss during transient regeneration mode. Presenter Seung-il Moon

Gasoline compression ignition (GCI) technology shows the potential to obtain high thermal efficiencies while maintaining low soot and NOx emissions in light-duty engine applications. Recent experimental studies and numerical simulations have indicated that high reactivity gasoline-like fuels can further enable the benefits of GCI combustion. However, there is limited empirical data in the literature studying the gasoline compression ignition process at relevant in-cylinder conditions, which are required for further optimizing combustion system designs. This study investigates the temporal and spatial evolution of the compression ignition process of various high reactivity gasoline fuels with research octane numbers (RON) of 71, 74 and 82, as well as a conventional RON 97 E10 gasoline fuel. A ten-hole prototype gasoline injector specifically designed for GCI applications capable of injection pressures up to 450 bar was used.

Recently, global warming and energy security have received significant attention. Thus an improvement of the vehicle fuel economy is strongly required. For engines, one effective way is to improve the engine thermal efficiency. Raising compression ratio [1] or turbo charging technologies have potential to achieve high thermal efficiency. However knock does not allow the high thermal efficiency. Knock depends on the fuel composition and the pressure and temperature history of unburnt end-gas [2-3]. For fuels, RON is well known for describing the anti knock quality. High RON fuels have high anti knock quality and result in higher thermal efficiency. This paper investigates the impact of high RON fuels on the thermal efficiency by using high compression ratio engine, turbo charged engine, and lean boosted engine [4]. Finally, it is shown that the high thermal efficiency can be approached with high RON gasoline and ethanol.

Feasibility studies concerning ethanol utilization in direct injection gasoline engines were conducted in order to clarify the effects of ethanol on engine performance, exhaust emissions and injector deposit formation. The investigation results indicate that E100 (100% ethanol fuel) can improve full load engine performance around whole engine speed range in a high compression ratio engine (ε=13:1), compared to that of a base compression ratio engine (ε=11.5:1) operated on a premium gasoline. This was caused by the volumetric efficiency (ηv) improvement and engine knock suppression in the high compression ratio engine. On the other hand, HC emissions remarkably increased under lower engine speeds at a full load condition. This phenomenon suggests that poor combustion occurred due to insufficient mixing of air and E100 fuel under these conditions, in which the amount of ethanol injected was too large and fluidity in the cylinder was weak.

From the viewpoint of primary energy diversification and CO2 reduction, interests of using Biomass Fuel are rising. Some kinds of FAME (Fatty Acid Methyl Ester), which are obtained from oil fats like vegetable oil using transesterification reaction with methanol, are getting Palm Oilpular for bio-diesel recently. In this study, we have conducted many experiments of palm oil hydrogenations using our pilot plants, and checked the reactivity and the pattern of product yields. As a result, we figured out that the hydrocarbon oil equivalent to the conventional diesel fuel can be obtained from vegetable oils in good yield under mild hydrogenation conditions. Moreover, as a result of various evaluations for the hydrogenated palm oil (oxidation stability, lowtemperature flow property, LCA, etc.), we found that the hydrogenated palm oil by our technology has performances almost equivalent to conventional diesel fuel.

From the energy security and CO2 discharge reduction point of view, much attention has been paid to the usage of biofuel, ethanol, as an alternative source of energy in the transportation industry. Yet, the major drawback in applying highly concentrated ethanol in the spark ignited internal combustion engines is cold start instability. This is due to the characteristics of ethanol, large latent heat required to vaporize. This paper investigates necessary conditions for the engine cold start, using highly concentrated ethanol. Tests performed with varieties of ethanol fuel, a relationship between cold startability lower temperature limit and reid vapor pressure was observed. A method to boost the vaporization, intake valve timing control is introduced to obtain high compression peak temperature.

In order to determine the main factors causing the mileage-related increase in formaldehyde emission from methanol-fueled vehicles, mileage was accumulated on three types of vehicle, each of which had a different air-fuel calibration system. From exhaust emission data obtained during and after the mileage accumulation, it was found that lean burn operation resulted in by far the highest formaldehyde emission increase. An investigation into the reason for the rise in engine-out formaldehyde emission revealed that deposits in the combustion chamber emanating from the lubricating oil promotes formaldehyde formation. Furthermore it was learnt that an increase in engine-out NOx emissions promotes partial oxidation of unburned methanol in the catalyst, leading to a significant increase in catalyst-out formaldehyde emission.

One-dimensional single-zone and two-zone analyses have been exercised to calculate the mass fraction burned in an engine operating on ethanol/gasoline-blended fuels using the cylinder pressure and volume data. The analyses include heat transfer and crevice volume effects on the calculated mass fraction burned. A comparison between the two methods is performed starting from the derivation of conservation of energy and the method to solve the mass fraction burned rates through the results including detailed explanation of the observed differences and trends. The apparent heat release method is used as a point of reference in the comparison process. Both models are solved using the LU matrix factorization and first-order Euler integration.

Biodiesel Fuel (BDF) Research Work Group works on identifying technological issues on the use of high biodiesel blends (over 5 mass%) in conventional diesel vehicles under the Japan Auto-Oil Program started in 2007. The Work Group conducts an analytical study on the issues to develop measures to be taken by fuel products and vehicle manufacturers, and to produce new technological findings that could contribute to the study of its introduction in Japan, including establishment of a national fuel quality standard covering high biodiesel blends. For evaluation of the impacts of high biodiesel blends on performance of diesel particulate filter system, a wide variety of biodiesel blendstocks were prepared, ranging from some kinds of fatty acid methyl esters (FAME) to another type of BDF such as hydrotreated biodiesel (HBD). Evaluation was mainly conducted on blend levels of 20% and 50%, but also conducted on 10% blends and neat FAME in some tests.

Considering the popularity of biodiesel fuels for diesel vehicles, the impacts of rapeseed oil methyl ester (RME), which is the most utilized biodiesel fuel in Europe, on tailpipe emissions from a diesel passenger car was investigated. In this study, 30% RME blended diesel fuel (RME30) was used and the comparison of tailpipe emissions between RME30 and a reference diesel fuel was conducted using a test vehicle with the latest engine and aftertreatment system. The results of the investigation reveal that RME30 generates about the same amount of NOx in tailpipe emissions as diesel fuel, and less HC, CO, and PM. These phenomena occurred in spite of attaching catalysts to the test vehicle, and therefore suggesting that the NOx conversion efficiency of the catalysts for RME30 is equal to that for diesel fuel. The injection rate for RME30 was the same as that for diesel fuel.

Previous studies have investigated the impacts of biofuel usage on the performance, drivability and durability of modern diesel engines and exhaust after-treatment systems including test work with different types, concentrations and mixtures of bio fuel components. During this earlier work vehicle fuel filter blocking issues were encountered during a field trial using various types of EN 14214 compliant Fatty Acid Methyl Ester (FAME) blended into EN 590 diesel. This paper summarises a subsequent literature review that was carried out looking into potential causes of this filter blocking and further work that was then carried out to expand on the findings. From this, a laboratory study was carried out to assess the increase in fuel filter blocking tendency (FBT) when various FAMEs from mixed sources were blended into EN 590 diesel at different concentrations, including levels above those currently allowed in the European market.

Dual fuel (CI) engines provide an excellent means of maintaining high thermal efficiency and power while reducing emissions, particularly in situations where the primary fuel does not exhibit good auto-ignition characteristics. This is especially true of diesel engines operating on natural gas; usually in stationary applications such as distributed power generation. However, because two fuels are needed, the reliability of the engine is compromised. Therefore, this paper describes the first phase of a project that is to eventually manufacture dimethyl ether (DME) from natural gas and supply it to the pilot injector of a dual fuel engine. A chemical pilot plant has been built and operated, demonstrating an intermediate step in the production of DME from natural gas. DME is manufactured from methanol for pilot injection into a dual fuel engine operating with natural gas as the main fuel.

Dimethyl Ether (DME) is considered a clean alternative fuel to diesel due to its soot-free combustion characteristics and its capability to be produced from renewable energy sources rather than fossil fuels such as coal or petroleum. To mitigate the effect of strong wave dynamics on fuel supply lines caused due to the high compressibility of DME and to overcome its low lubricity, a hydraulically actuated electronic unit injector (HEUI) with pressure intensification was used. The study focuses on high pressure operation, up to 2000 bar, significantly higher than pressure ranges reported previously with DME. A one-dimensional HEUI injector model is built in MATLAB/SIMULINK graphical software environment, to predict the rate of injection (ROI) profile critical to spray and combustion characterization.

Despite the fact that methanol is toxic to human health and causes serious damage to automobile engines and fuel system components, methanol-containing gasoline is becoming popular in some areas. Methanol demonstrates similar chemical properties to ethanol (which is already established as an additive to gasoline), so that it is difficult to identify methanol-containing gasoline without performing proper chemical analysis. In this study, we report a low-cost, portable, and easy-to-operate sensor that selectively changes color in response to methanol contained in gasoline. The colorimetric sensor will be useful for automobile users to avoid methanol-containing gasoline upon refueling.

It is beneficial but challenging to operate spark-ignition engines under highly lean and dilute conditions. The unstable ignition behavior can result in downgraded combustion performance in engine cylinders. Numerical approach is serving as a promising tool to identify the ignition requirements by providing insight into the complex physical/chemical phenomena. An effort to simulate the early stage of flame kernel initiation in lean and dilute fuel/air mixture has been made and discussed in this paper. The simulations are set to validate against laboratory results of spark ignition behavior in a constant volume combustion vessel. In order to present a practical as well as comprehensive ignition model, the simulations are performed by taking into consideration the discharge circuit analysis, the detailed reaction mechanism, and local heat transfer between the flame kernel and spark plug.

A model process to produce dimethylether (DME) from natural gas (NG) was simulated in a one-pass mode (no material recycle), assuming steady-state and chemical and physical equilibrium. NG conversion to synthesis gas (syngas) via steam reforming resulted in stoichiometric numbers of 2.97 along with vapor mole fraction extremes for carbon dioxide, methane, and water. These concentrations formed an eight-trial simulation grid of syngas compositions. Simulation of DME production was performed in a dual reactor configuration with methanol formation as the intermediate compound. Solutions resulting from the subsequent adiabatic dehydration of the methanol-rich phase showed a consistent DME composition (88%). The resulting solutions and unreacted syngas streams from simulation were examined for applicability to a dual-fuel NG/DME CI engine.

The characteristics of combustion knock metrics over a number of engine cycles can be an essential reference for knock detection and control in internal combustion engines. In a Spark-Ignition (SI) engine, the stochastic nature of combustion knock has been shown to follow a log-normal distribution. However, this has been derived from experiments done with gasoline only and applicability of log-normal distribution to dual-fuel combustion knock has not been explored. To evaluate the effectiveness and accuracy of log-normal distributed knock model for methane-gasoline blended fuel, a sweep of methane-gasoline blend ratio was conducted at two different engine speeds. Experimental investigation was conducted on a single cylinder prototype SI engine equipped with two fuel systems: a direct injection (DI) system for gasoline and a port fuel injection (PFI) system for methane.

The effects of biodiesel oxidation stability on diesel fuel injection equipment (FIE) behavior were investigated using newly developed test rig and methodology. On the test rig, biodiesel blend fuels were circulated through a fuel tank and a common rail injection system. Fuel injected from typical diesel injectors was returned into the fuel tank to enhance the speed of fuel degradation. The results showed that injector deposits could be reproduced on a test rig. It was observed that injector body temperature increase accelerates the degradation of fuel and therefore gives earlier FIE failure. Fuel renewal could partially restore the injection quantity after complete failure at low injection pressure, thus showing a potential cleaning effect on injector deposits when refueling a car.

A 2007 Cummins ISL 8.9L direct-injection common rail diesel engine rated at 272 kW (365 hp) was used to load the filter to 2.2 g/L and passively oxidize particulate matter (PM) within a 2007 OEM aftertreatment system consisting of a diesel oxidation catalyst (DOC) and catalyzed particulate filter (CPF). Having a better understanding of the passive NO₂ oxidation kinetics of PM within the CPF allows for reducing the frequency of active regenerations (hydrocarbon injection) and the associated fuel penalties. Being able to model the passive oxidation of accumulated PM in the CPF is critical to creating accurate state estimation strategies. The MTU 1-D CPF model will be used to simulate data collected from this study to examine differences in the PM oxidation kinetics when soy methyl ester (SME) biodiesel is used as the source of fuel for the engine.

Higher carbon number alcohols offer an opportunity to meet the Renewable Fuel Standard (RFS2) and improve the energy content, petroleum displacement, and/or knock resistance of gasoline-alcohol blends from traditional ethanol blends such as E10 while maintaining desired and regulated fuel properties. Part II of this paper builds upon the alcohol selection, fuel implementation scenarios, criteria target values, and property prediction methodologies detailed in Part I. For each scenario, optimization schemes include maximizing energy content, knock resistance, or petroleum displacement. Optimum blend composition is very sensitive to energy content, knock resistance, vapor pressure, and oxygen content criteria target values. Iso-propanol is favored in both scenarios' suitable blends because of its high RON value.