• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.135-143
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• 2013

In this study, we suggested effective countermeasure of biodiesel oxidation problems by investigating the oxidation degradation of biodiesels derived from variable resources and the level of oxidation stability of current distributing biodiesel blended fuels (2%) in Korea, and oxidation stability change according to storage time (for 3 month) and biodiesel blending ratio (2, 5, 7, 10%). By the composition analysis results of biodiesel from various resources which are possible to distribute in Korea, the biodiesel from animal fat has poor oxidation stability and cold performance, while the biodiesel from coconut and palm kernel which are considered as future potential raw material showed good oxidation stability and cold performance. The oxidation stability level of current distributing biodiesel blended fuels in Korea was excellent with showing over 30 hours (average 68 hours) stability, but the oxidation stability of the blended fuel with animal fat biodiesel having poor oxidation property (1.22 hours) was rapidly decreased to below 32 hours by mixing only 2%. Therefore, we have to pay attention to quality control of oxidation property, because the oxidation stability problem can be caused by increasing biodiesel blending ratio and diversifying raw materials those have worse property.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.28 no.1
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• pp.45-52
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• 1992

In this paper, combustion characteristics and engine performance varying with blending rate of fish oil using five test fuels, e.g.pure diesel oil and four types of sardine-oil-blended diesel oils, their blending rates by weight being 20%, 40%, 60% and 80% respectively, and operating condition of engine, were investigated experimentally both in the constant volume combustion bomb and in the engine. The results are summarized as follows: 1) In the bomb, the influence of temperature on ignition delay of sardine-oil-blended diesel oils was larger than that of pure diesel oil, and it tended to increase as the blending rate of fish oil increase sardine-oil-blended diesel oils. As far as the influence of pressure on ignition delay concerns, there was no significant difference with all the test fuels. 2) In the engine, the ignition delay of fish-oil- blended diesel oils was longer than that of pure diesel oil, and it tended to increase as the blending rate increases. In the bomb, the ignition delay in high temperature showed no significant difference between with pure diesel oil and with fish-oil-blended diesel oils, and it was especially short with 60% fish-oil-blended diesel oil. In low temperature, however, the delay became longer as the blending rate increase. 3) The combustion duration was shorter with fish-oil-blended diesel oils than with pure diesel oil and it became a little shorter as the blending rate increases. 4) The rate of fuel consumption showed no significant difference between with fish-oil-blended diesel oils and with prue diesel oil, although calorific value of fish oil was lower than that of diesel oil. 5) Smoke density in exhaust gas was lower with fish-oil-blended diesel oils than with pure diesel oil and the higher the blending rate was, the lower the smoke density became.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.4
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• pp.92-102
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• 2001

The effect of ethanol-blending on the performances of the MPI gasoline engine was examined. The experiments were carried out for the stoichiometric conditions under MBT spark timing over various operating conditions. The blending rate of ethanol were determined as 10 to 30 percent according to the analysis of the properties of blended fuels. The engine with ethanol-blended fuels showed improved performances such as brake torque, brake power, brake thermal efficiency and exhaust emissions compared with those of pure gasoline over most operating conditions. Though the brake specific fuel consumption was increased by ethanol-blending due to their lower heating values, the increasing rates of the brake specific fuel consumption were limited to the half of the blending rates owing to the increase in the thermal efficiency.

• International Journal of Automotive Technology
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• v.6 no.3
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• pp.197-203
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• 2005

This paper investigates the effect of oxygen composition in mixed fuel on the exhaust emissions for the direct injection diesel engine. These effects were tested to estimate the change in engine performance and exhaust emission characteristics when commercial diesel fuel and oxygenates blended fuels at a certain fuel and mixed ratio are used. Individual hydrocarbons $(C_1-C_6)$ in exhaust gases, as well as the total amount of hydrocarbons, were analyzed by using gas chromatography to find the mechanism by which smoke emission was remarkably reduced for various oxygenated fuels. The chromatograms between a diesel fuel and a diesel fuel blended DGM (diethylene glycol dimethyl ether), MTBE (methyl tert-butyl ether) and EGBE (ethylene glycol mono-n-butyl ether) were compared. The results showed that the number of individual hydrocarbons as well as the total number of hydrocarbons of oxygenated fuel reduced more remarkably than those of diesel fuel.

• Journal of ILASS-Korea
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• v.18 no.4
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• pp.169-175
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• 2013

Hydrotreated biodiesel (HBD) would be one of the promising alternative fuels instead of current biodiesel. In this study, spray characteristics in terms of spray penetration and spray angle were conducted experimentally including calculated SMDs as well. The ambient pressures of 1, 3, and 5 MPa and injection pressures of 30, 80, and 130 MPa were introduced and the fuels employed were petro-diesel, and 2, 10, 20, 30, and 50% for hydrotreated biodiesel, respectively. The result of this study found that the more HBD blended diesels have the slightly shorter spray tip penetration lengths especially on the lowest injection pressure and at the highest ambient pressure, but have the larger spray angles and SMDs than petro-diesel. Consequently, this study found that HBD has a little bit merits and demerits of macro- and micro- spray patterns compared to petro-diesel.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.5
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• pp.530-537
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• 2012

This work experimentally investigates that Diesel-DME blended fuel influences combustion characteristics and emissions (NOx, CO, HC, smoke) in a single-cylinder DI diesel engine. Diesel is used as a main fuel and DME is blended for the use of its quick evaporating characteristics. Diesel and DME are blended by the method of weight ratio. Weight ratios for Diesel and DME are 95:5 and 90:10 respectively and the both ratios have been used altogether in blended fuel. The experiments are conducted in this study single cylinder engine is equipped with common rail and injection pressure is 700 bar at 1200 rpm. The amount of injected fuels is adjusted to obtain the fixed input calorie value as 972.2 J/cycle in order to compare with the fuel conditions. DME is compressed to 15 bar by using nitrogen gas thus it can be maintained the liquid phase. In this study, different system compared others paper is common rail system, also there is combustion and emission about compared DME and diesel fuel. It is expected to be utilized about blended fuel.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.8
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• pp.813-820
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• 2015

Straight vegetable oil (SVO) is widely recommended as fuel for diesel engines in general and especially for marine diesel engines. However, SVOs used directly as fuel for diesel engines may cause problems for the engines; SVOs blended with diesel oil are a better choice. To widen understanding of the possibility of using blended SVOs as fuel alternatives, this paper presents results of experimental research on the combustion of blended straight vegetable oil in a marine diesel engine's cylinders. Results show that the fuel combustion process have the same curves as in simulations and, in the case of using blended fuels with up to 20% palm oil, the test diesel engine technical parameters such as engine output, exhaust gas temperatures, and specific fuel consumption are very similar to those of diesel oil (DO). Based on these results, marine diesel engines are strong potential applications and particularly recommended for the use of SVO blends.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.3
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• pp.516-521
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• 2004

In this paper, the effects of ethanol blended gasoline on emissions and their catalytic conversion efficiencies characteristics were investigated in gasoline engine with an electronic fuel injection. The results showed that the increase of ethanol concentration in the blended fuels brought the reduction of THC and $CO_2$ emissions from the gasoline engine. THC emissions were drastically reduced up to thirty percent. And brake specific fuel consumption was increased. but brake specific energy consumption was similar level. However. unburned ethanol and acetaldehyde emissions increased. The conversion efficiency of Pt/Rh based three-way catalysts and the effect of ethanol on CO and NOx emissions were investigated by the change of engine speed. load and air/fuel ratio. Furthermore, the ethanol blended fuel results in the reduction effect of THC. CO and NOx emissions at idle speed.

• Journal of ILASS-Korea
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• v.25 no.3
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• pp.111-118
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• 2020

This paper describes the effect of DME, biodiesel blended fuels on the macroscopic spray characteristics in a high pressure diesel injection system using Background Oriented Schlieren (BOS) method. The BOS method for visualization of impingement evaporation sprays to analyze macroscopic spray properties and evolutionary processes. In this work, the blending ratio of DME in the blended fuel are 0, 50, 100% by weight ratio. In order to investigate the macroscopic impinged spray characteristics under the various injection parameters and blending ratio. In this work, a mini-sac type single-hole nozzle injector with nozzle hole was length 0.7 mm and diameter of 0.3 mm was used. According to the result, the spray area of the collision wall increased as the DME mixing ratio increased, and the evolutionary pattern showed a stepwise increase due to the collision effect of the wall. Also, results of impinged spray area were increased according to increasing injection pressure.

• Journal of Power System Engineering
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• v.4 no.3
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• pp.12-18
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• 2000

Recently, our world is faced with very serious and hard problems related to the air pollution due to the exhaust emissions of the diesel engine. So, lots of researchers have studied to reduce the exhaust emissions with various methods of diesel engine that influenced the environment strong. In this paper, the quantities of the low and high hydrocarbon among the exhaust emissions in diesel engine have been investigated by the quantitative analysis of the hydrocarbon $C_1{\sim}C_6$ using the gas chromatography. This study carried out by comparing the chromatogram with diesel fuel and three kinds of mixed fuels. One is the diesel fuel blended DGM(diethylene glycol dimethyl ether) 5%. Another is the diesel fuel blended DEE(diethyl ether) 25% and DMC(dimethyl carbonate) 10%. The results of this study show that the hydrocarbon $C_1{\sim}C_6$ among the exhaust emissions of the mixed fuels are exhausted lower than those of the diesel fuel at the all load and speed.