• 한국자동차공학회논문집
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• 제16권1호
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• pp.152-157
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• 2008

The biodiesel becomes one of the favorite alternative fuel applied to diesel engines. This research aims to understand the physics of spray and combustion characteristics of a biodiesel fuel in a constant volume chamber. For spray visualization, biodiesel was injected into a combustion chamber and a high speed camera was applied at various combustion conditions. To investigate heat-release rates and flame propagations, spark was ignited on a hydrogen fuel for the premixed combustion and then biodiesel was injected directly. In addition, parametric study was made by various geometries of combustion chambers and temperatures of fuels and injection pressures. This technology may contribute to improve the performance of bio-diesel engine and reduce emissions in future.

• 동력기계공학회지
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• 제17권6호
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• pp.25-32
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• 2013

Biodiesel is technically competitive with it and offers technical advantages over conventional petroleum diesel fuel. Biodiesel is an environment friendly alternative liquid fuel that can be used in any diesel engine without modification. In this study, (dP/dCA)max and heat release, emission characteristics with different fuel injection timings are compared between diesel fuel and biodiesel in the D.I. diesel engine with T/C. The engine was operated at five different fuel injection timings from BTDC 6deg to 14deg at 2deg intervals and with four different loads at engine speed of 1800rpm. The experiments in a test engine showed that ranges between low and high of (dP/dCA)max got narrower, as the engine load increased, BD blend rate increased, and fuel injection timing was delayed. Cumulative heat release increased with the advanced fuel injection timing. NOX emissions decreased with the delays of fuel injection timing.

• 동력기계공학회지
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• 제12권1호
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• pp.5-12
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• 2008

We measured emission characteristics of CRDI diesel engine equipped with a commercial CPF. Experimental parameters adopted a neat diesel fuel, a blend of diesel fuel with 20% biodiesel, a blend of diesel fuel with 15% biodiesel and 5% ethanol. The experiments were carried out to measure the emission and engine performance according to ESC 13-mode cycles. The maximum torque with biodiesel blend fuel is slightly lower than that of neat diesel fuel in the entire the 13-mode cycles, and 5% ethanol and 15% biodiesel blend fuel is slightly higher than that of neat diesel fuel. THC and CO emissions of the biofuel blended diesel fuel were slightly increased and decreased, and mean conversion efficiencies of THC and CO on the commercial CPF were achieved about 70$\sim$87% in the ESC 13-mode. From the measurement by the Scanning Mobility Particle Sizer(SMPS), the total number and mass of nano-sized particles by a commercial CPF were decreased about 97.8% and 96.8 % in the range of the nano-size from 10.6 to 385nm, respectively.

• Journal of Biosystems Engineering
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• 제33권2호
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• pp.124-129
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• 2008

In this study, fuel qualities including kinematic viscosity and pour point in the various temperature, calorific value and combustion characteristics of two biodiesels based on the soybean and waste oil blended with light oil were investigated and discussed in order to figure out to confirm fuel compatibility taking the place of light oil in the hot air heater or boiler. As biodiesel content ratio increased calorific value of biodiesel decreased, and the difference was 13% between 100%-biodiesel and light oil. In general, pour points of the biodiesels were higher than light oil, and as biodiesel content ratio increased pour point increased. About 15 cSt was the pour point of biodiesels and light oil, which occurred at 3 to $4^{\circ}C$ in the biodiesels and $-25^{\circ}C$ in the light oil. Flame dimensions of biodiesels and light oil were almost same at the same combustion condition in the burner of the hot air heater. CO concentrations in the exhaustion gas were far lower than those of the light oil. Though pour point of biodiesel is a little inferior to light oil, still biodiesel can be an alternative fuel substituting for light oil in combustion system without much modifying the current oil combustion mechanism.

• 농업과학연구
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• 제46권4호
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• pp.941-953
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• 2019

Biodiesels are being explored as a clean energy alternative to regular diesel, which causes pollution. In this study, the optimum conditions for producing biodiesel (BD) by combining beef tallow, an animal waste resource with a high saturated fatty acid content, and corn oil, a vegetable oil with a high unsaturated fatty acid content, were investigated, and the fuel properties were analyzed. Furthermore, Multivariate Analysis of Variance (MANOVA) was used to verify the optimum conditions for producing biodiesel. The influences of control factors, such as the oil blend ratio and methanol to oil molar ratio, on the fatty acid methyl ester and biodiesel production yield were investigated. As a result, the optimum condition for producing blended biodiesel was verified to be tallow to corn oil blend ratio of 7 : 3 (TACO7) and a methanol to oil molar ratio of 14 : 1. Moreover, the interaction between the oil blend ratio and the methanol to oil molar ratio has the most crucial effects on the production of oil blended biodiesel. In conclusion, the analysis results of the fuel properties of TACO7 BD satisfied the BD quality standard, and thus, the viability of BD blended with waste tallow as fuel was verified.

• 농업과학연구
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• 제47권1호
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• pp.29-41
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• 2020

Biodiesel is a clean energy resource that can replace diesel as fuel, which can be used without any structural changes to the engine. Vegetable oil accounts for 95 percent of the raw materials used to produce biodiesel. Thus, many problems can arise, such as rising prices of food resources and an imbalance between supply and demand. Most of the previous studies using waste cooking oil used waste cooking oil from a single material. However, the waste cooking oil that is actually collected is a mixture of various types of waste cooking oil. Therefore, in this study, biodiesel produced with mixed waste cooking oil was supplied to an agricultural single-cylinder diesel engine to assess its potential as an alternative fuel. Based on the results, the brake specific fuel consumption (BSFC) increased compared to diesel, and the axis power decreased to between 70 and 99% compared to the diesel. For emissions, NO_x and CO₂ were increased, but CO and HC were decreased by up to 1 to 7% and 16 to 48%, respectively, compared to diesel. The emission characteristics of the mixed waste cooking oil biodiesel used in this study were shown to be similar to those of conventional vegetable biodiesel, confirming its potential as a fuel for mixed waste cooking oil biodiesel.

• 한국산학기술학회논문지
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• 제15권6호
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• pp.3383-3388
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• 2014

본 연구는 4실린더 커먼레일 디젤 기관에서 바이오디젤 혼합 연료와 순수한 디젤연료를 사용하여 EGR율을 변화시켰을 때 연소 및 배기 특성을 디젤 연료만을 사용하였을 경우와 비교하기 위하여 실험을 수행하였다. 본 연구에서는 일반적으로 많이 사용되고 있는 기관 회전 속도 2,000rpm에서 바이오디젤 혼합율 20%의 연료와 디젤 연료를 사용하여, EGR율에 다양하게 변화를 주어 실험을 하였다. 실험결과, 연소압력은 바이오디젤 혼합 연료와 디젤 연료 모두 EGR율이 증가할수록 감소하였으며, 도시 평균유효 압력은, 디젤 연료에 비하여 바이오디젤 혼합 연료가 더 높게 나타났다. 배출가스의 경우에, NOx는 EGR율이 증가할수록 디젤 연료에 비하여 바이오디젤 혼합 연료가 더 많이 배출되었다. 또한 NOx는 바이오디젤 혼합 연료와 디젤연료 모두 EGR율이 증가할수록 감소되었다. CO와 Soot, $CO_2$는 EGR율이 증가 할수록 증가하였으며, CO, Soot은 디젤 연료에 비해 바이오디젤 혼합 연료에서 더 작게 배출되었지만 $CO_2$는 더 많이 배출되었다.

• 한국분무공학회지
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• 제14권4호
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• pp.153-162
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• 2009

The use of inedible vegetable oils as substitute for diesel fuel in compression ignition engine is of significance because of the great need for edible oil as food, and the reduction of biodiesel production cost etc. Jatropha curcas oil which is a leading candidate for the commercialization of inedible vegetable oils is selected in this study for reviewing the application in CI engine as an alternative fuel. The important properties of jatropha oil (JO) and JO biodiesel are summarized from the various sources in the literature. It is found that five different types of alternative fuel from JO such as neat JO, JO blends with diesel or other fuel, neat JO biodiesel, JO biodiesel blends with diesel or other fuel and degummed JO were extensively examined in the diesel engine. Two different application types of alternative fuels from JO such as preheating and dual fuelling were also tested, It should be pointed out that most of these applications are limited to single cylinder conditions. The systematic study for the selection of effective application method is required. It is clear that the blends of JOME and diesel can replace diesel fuel up to 10% by volume for running the existing common rail direct injection systems without any durability problems. The systematic assessment of spray characteristics of different types of JO and its derivatives for use as diesel engine fuel is also required.

• Journal of Biosystems Engineering
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• 제38권3호
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• pp.208-214
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• 2013

Purpose: Performances of a tractor diesel engine fueled by three different animal fats biodiesels were evaluated comparing with light oil tractor in terms of power, fuel consumption rate, exhaust gases, particulate matter amount and field work capacity. Methods: Animal fats based on pig biodiesel were manufactured manually and tested for its engine performance in the tractor diesel engine and fuel adoptability in the field works. Four different fuels, three different content of biodiesel (BD20, BD50, BD100) and light oil, were prepared and tested in the four strokes diesel engine. Power output, fuel consumption rate and exhaust gases of the four fuels in the diesel engine were compared and discussed. Results: Power output of light oil engine was the greatest showing 5.3% difference between light oil and BD100, but 0.37% better power than BD20 engine power. Less exhaust gases of $CO_2$, CO, $NO_X$ and THC were produced from animal fats biodiesel than light oil, which confirmed that biodiesel is environmental friendly fuel. For fuel adoptability in the tractor, biodiesel engine tractor showed its fuel competitiveness comparing with light oil for tractor works in the faddy field. Conclusions: With four different fuel types of animal-fats biodiesel, performances of a four cylinder diesel engine for tractor were evaluated in terms of power, exhaust gases, particulate matters (PM) and field work capacity. No significant differences observed in the engine performances including power output and exhaust gases emission rate. No significant power difference observed between the various fuels including light oil on the engine running, however, amounts of noxious exhaust gases including $CO_2$ and $NO_X$ decreased as biodiesel content increased in the fuels. Field performances of animal-fats biodiesel tractor were investigated by conducting plowing and rotary operation in the field. Tilling and rotary performance of light oil tractor and BD20 tractor in the field were compared, in which about 10% travelling speed difference on both operations were monitored that showed light oil tractor was superior to BD20 tractor by 10%. Animal-fats can be an alternative fuel source replacing light oil for agricultural machinery and an environmental friendly fuel to nature.

• 한국분무공학회지
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• 제16권1호
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• pp.15-26
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• 2011

In this article, spray characteristics in CI engines fuelled with vegetable oils and its derivatives will be reviewed. Of edible vegetable oils, soybean oil and rapeseed oil were mainly investigated. Of inedible vegetable oils, jatropha oil and used frying oil were main concern on the research on the spray characteristics in CI engine. Spray angle and spray penetration were mainly examined among the macroscopic spray characteristics and Sauter mean diameter was only investigated among the microscopic spray characteristics. There exist six different definitions of spray angle which should be examined. Neat vegetable oil and biodiesel fuels show smaller spray angle than diesel fuel. Biodiesel fuel and vegetable oils and its blend have a longer spray penetration than diesel fuel. However, biodiesel blends with diesel shows the similar spray penetration with diesel fuel. SMDs in the biodiesel spray, vegetable oils and its blends spray are higher than that in the diesel spray.