• Tribology and Lubricants
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• v.33 no.1
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• pp.23-30
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• 2017

The electric controlled marine diesel engine has fuel pump generating the high pressurized fuel for fuel injection to combustion chamber via a common rail. Fuel pump consists of a cam-roller system. Journal bearing installed between a roller and a cam-roller pin is subjected to fluctuating heavy and instant loads by cam lift. First, Kinematic analysis is carried out to predict bearing loads during one cycle acting on the journal bearing. Second, flexible multi-body dynamic analysis and transient elasto-hydrodynamic(EHD) lubrication analysis for journal bearing considering elastic deformation of cam-roller pin, roller and bearing are conducted using AVL EXCITE/PU software to predict lubrication performance. The clearance ratio and journal groove shape providing lubrication oil are important parameter in bearing design having good performance and can be changed easier than other design parameters such as diameter, width, oil supply pressure and bearing material grade. Generally, journal bearing performance is represented by the minimum oil film thickness(MOFT) and peak oil film pressure(POFP). As well as the traditional design parameters(MOFT, POFP), in this study, temperature rise of lubrication oil is also evaluated through the side leakage flow of supplied oil. By the evaluating MOFT, POFP and temperature rise, the optimum bearing clearance ratio is decided.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.11-18
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• 2003

This study was carried cut to get basic data of troubles in starting and supply of farm diesel engines in cold winter. The results of the study are summarized as follows: 1. As the result of farm survey. the proportions of farms which had starting problems or troubles in fuel supply in cold winter for the last 5 years were 38% for the farms with power-tillers and 32% for the farms with tractors. Most of the farms which had starting problems or troubles in fuel supply in cold winter used light oil for summer. spring or fall rather than for winter. 2. As the result of fuel supply test, fuel supply was stopped at -6$^{\circ}C$ and -18$^{\circ}C$ for summer light oil and winter light oil. respectively 3. The lowest temperatures of winter light oil for starting engine were -7.5$^{\circ}C$ for power-tiller. -12.5$^{\circ}C$ for tractor of 38ps, and -17.5$^{\circ}C$ for tractor of 45ps. which were 5~7.5$^{\circ}C$ lower than that of summer light oil. 4. The performance of engine starting and the trouble of fuel supply system at lower temperature were significantly improved by using winter hight oil rather than summer light oil.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.37-44
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• 2003

To know the penetration behavior of spilled oil into sandy beach sediment is very important, because the penetration depth of the stranded oil into the sediments is one of the most significant information to know effect of spilled oil on biological communities and to set up cleaning method. The purpose of this study is to clarify the effects of wave and/or tidal action on penetration of spilled oil into the sediments and to clarify main factor in oil penetration using sandy beach model. Specific conclusions derived from this study are as follows. Spilled fuel oil C penetrated into the sediments only by falling tidal fluctuation and not by wave action on sandy beach environment, and the first tide is most important for the penetration of stranded oil. Over 80% of bulk fraction in penetrated fuel oil C was concentrated to the top 2 cm sediment-layer. Moreover, the penetration of stranded oil into the sandy beach sediments was strongly correlated with the oil viscosity affected by temperature.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.137-146
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• 2007

The substitution of fossil fuels with biofuels has been proposed by the European Union (EU) as part of a strategy to mitigate greenhouse gas emissions from road transport, increase security of energy supply and support the development of rural communities. Vegetable oils and their derivatives (especially methyl esters), commonly referred to as 'biodiesel', are prominent candidates as alternative diesel fuels. They have advanced from being purely experimental fuels to the initial stages of commercialization. They are technically competitive with or offer technical advantages compared to conventional diesel fuel. However, several problems remain including economics, combustions, some emissions, lube oil contamination, and low-temperature properties. Therefore, quality control of fuel-related properties of biodiesel is needed to obtain consistent engine performance by fuel users. The quality of the fuel is affected by the oil composition. Rapeseed oil has been targeted for fuel use because it produces an oil with a close-to-optimum set of fuel characteristics. In this paper we have reviewed past and current efforts, both by traditional seed-breeding methods and by genetic engineering, to modify rapeseed oil quality and yield.

• Applied Chemistry for Engineering
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• v.28 no.2
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• pp.186-192
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• 2017

In this study, water in oil (W/O) emulsion fuel was prepared with surfactant mixture of OIMS90 and NP12 by varying ratio of water to bunker-C oil, surfactant concentration and composition, emulsification time, stirring intensity, temperature and mixing time. Diesel engine performance and exhaust emissions were measured and analyzed with prepared emulsified fuel and compared with those measured using bunker Coil. The results indicated that bunker C emulsion fuel stabilized by surfactant mixture of OIMS90 and NP12 is efficient in reducing emissions of particulate matter, $NO_2$, CO, $CO_2$ and $SO_2$. The biggest reduction in exhaust emission was achieved by using emulsion fuel prepared by OIMS90/NP12 = 4 : 6, 500 ppm of total surfactant concentration and 10% water content at $80^{\circ}C$. Boiler efficiency test measured with emulsion fuel showed excellent energy efficiency compared with bunker C oil.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.381-386
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• 2015

Environmental pollution and alternative energy has attracted increasing interest. The use of diesel engines is expected to increase in the world owing to their fuel economy. The problem of air pollution emissions from marine engines is causing a major concern in many areas. An alternative fuel was introduced as an environmentally friendly fuel to reduce the toxic emissions from conventional fossil fuels. Biodiesel fuel, which is a renewable energy is highlighted as environmentally friendly energy. This energy can be operated in regular diesel engines when it is blended with invariable ratios without making changes. In this study, a bio-diesel fuel was produced from waste cooking oil and applied to a marine diesel engine to examine the effects on the characteristics of combustion. Waste cooking oil contains a high cetane number and viscosity component, a low carbon and oxygen content. As a result, the brake specific fuel consumption was increased, and the cylinder pressure, rate pressure rise and rate of heat release were decreased.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.6
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• pp.754-762
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• 1998

Exhaust emissions in diesel engine are affected by fuel properties but the reason for this is not clear. Especially the recent strong interest in using low-grade fuel demands extensibe investigation in order to clarify the exhaust emissions. Bio-Diesel oil has a great possibility to solve the pollution problem caused by the exhaust gas from diesel engine vehicles. The use of bio-oils in diesel engines has received considerable atten-tion to the forseeable depletion of world oil supplies. So bio-diesel oil has been attracted with attentions for alternative and clean energy source. The purpose of this paper is to evaluate the fea-sibility of the rice-bran oil for alternative fuel in a diesel engine with rgard to exhaust emis-sions.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.1
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• pp.53-58
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• 2013

In order to judge that non-esterified soybean oil could be used on diesel engine with electronic control of fuel injection system, The test of combustion performance using only gas oil, gas oil blended with esterified bio-diesel oil 5% and non-esterified soybean oil 5% were carried out. It is noticed that most performances of gas oil blended with esterified bio-diesel oil 5% and non-esterified 5% have similar characteristics but non-esterified bio-diesel oil 5% emitted smaller NOx, resulting from fuel NO.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.554-563
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• 2016

Ships are capable of operating on residual fuel oil. Recently, various attempts have been made to meet environmental regulations and with ships operating on residual fuel oil. One way of fulfilling these requirements is by using fuel additives. Dispersants and fuel combustion improvers will have a positive effect on improving the combustion characteristics of the residual fuel oil. As such, this study examines fuel oils blended with additives by using fuel combustion analysis (FIA/FCA) and thermogravimetric analysis (TGA). The results of FIA/FCA focuse only on the amount of work done by the fuel oil. Therefore, it is recommended in this study that a new method to evaluate the combustion efficiency via FIA/FCA processes be developed. The analysis with ROHR curve gained by FIA/FCA brought similar results with pressure trace curve therefore it can be said that new analysis method can be reliable. The TGA, analysis process is very sensitive to the evaporation of fuel, for example, which could be addressed. In the performance-related findings of this study, blended samples with additives containing iron compounds showed a greater improvement in early combustion characteristics than samples without additives.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.103-108
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• 2015

Recent global warming has been recognized as the world economy development from fossil fuel use is the culprit. This study was reduce the fossil fuel has been developed in a number of alternative energy, As a fuel that can be produced in our country is a biofuel. Biofuels is a sustainable fuel having economically benefits and decreasing environmental pollution problems caused due to fossil fuel. A lot of research is progressing about the conversion of diesel biofuel as renewable clean energy. In this experiment were remodel the institution that has been used in fishing engine again produced an experimental apparatus were installed directly, were studied using various bio fuel like to help the economically and environmentally sound operation of the vessel. rapeseed oil, soybean oil, comprehensively analyzing the results the effects of the exhaust emission characteristics of the waste rapeseed oil is available in a marine engine with similar physical and chemical components of the fuel, and the fuel consumption ratio, NOx is slightly increased, but soot was confirmed a tendency to decrease much.