• 한국자동차공학회논문집
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• 제14권3호
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• pp.103-111
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• 2006

The spray behavior of direct-injection spark-ignition(DISI) engines is crucial for obtaining the required mixture distribution for optimal engine combustion. The spray characteristics of DISI engines are affected by many factors such as piston bowl shape, air flow, ambient temperature, injection pressure and fuel temperature. In this study, the effect of fuel temperature on the spray and combustion characteristics was partially investigated for the wall-guided system. The effect of fuel temperature on the fan spray characteristics was investigated in a steady flow rig embodied in a wind tunnel. The shadowgraphy and direct imaging methods were employed to visualize the spray development at different fuel temperatures. The microscopic characteristics of spray were investigated by the particle size measurements using a phase Doppler anemometry(PDA). The effect of injector temperature on the engine combustion characteristics during cold start and warming-up operating conditions was also investigated. Optical single cylinder DISI engine was used for the test, and the successive flame images captured by high speed camera, engine-out emissions and performance data have been analyzed. This could give the way of forming the stable mixture near the spark plug to achieve the stable combustion of DISI engine.

• 한국수소및신에너지학회논문집
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• 제20권2호
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• pp.161-167
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• 2009

The regulation of the $CO_2$ emit from vehicles have become much more stringent in recent years. This stringent regulation is more request vehicle manufacturers to develop the alternative fuel vehicles for reducing exhaust emissions. LPG fuel is more clean energy compares with gasoline and diesel fuel. Especially, $CO_2$ emission of LPG Vehicle is less than gasoline vehicle and almost equal to diesel vehicle. For this reason, recently korean government is extending LPG fuel for hybrid car and light duty vehicle. In domestic, Propane is mixing $15{\sim}30%$ to butane for improvement of cold start at winter season. Therefore, In this paper was investigated that the characteristics of emissions according to propane mixing rate with 0, 10, 20, 30% were compared and analyzed by the vehicle test using LPG vehicle according to the FTP75 mode. It was also investigated the characteristics of nano-particle emit with propane mixing rate.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.74-79
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• 2006

Good cold start characteristics are essential for satisfactory operation of fuel cell vehicles. In this study, the melting process has been numerically investigated for a water tank frozen in cold weather The 2-D model of the tank containing ice and plate heaters was assumed and the unsteady melting process of the ice was calculated. The enthalpy method was used for the description of the melting process, and a FVM code was used to solve the problem. The feasibility study compared with other experiment showed that the developed program was able to describe the melting process well. From the numerical analysis carried out for different wall temperatures of the pate heaters, some important design factors could be found such as local overheating and pressurization in the tank.

• 공업화학
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• 제21권6호
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• pp.653-658
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• 2010

바이오디젤은 기존석유디젤을 대체할 수 있는 친환경적인 연료로 알려져 있다. 하지만 원료물질이 대부분 가격이 높은 식량자원을 이용한다는 단점을 지니고 있다. 본 연구에서는 음식쓰레기로 생긴 오리기름을 전처리 한 후, 염기촉매를 이용하여 전이에스테르화 반응을 통해 바이오디젤을 합성하였다. 합성되어진 바이오디젤의 대표적 연료특성으로 밀도, 동점도, 저온특성, 윤활성, 세탄가를 분석한 결과, 국내에서 동절기 외에는 충분히 석유대체연료로 사용 가능하다는 결과를 얻었다.

• 한국분무공학회지
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• 제16권2호
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• pp.76-81
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• 2011

A fuel injection system which is operated with a real vehicle driving simulation was developed as an alternative to a vehicle test for the fuel injectors. The sensor signals that are supplied to the ECU were measured and recorded as a data file for a vehicle driven in FTP-75 mode in a chassis dynamometer. The imperative sensor signals of the throttle position, vehicle speed, engine speed, crank position, cam position, intake air flow, and cooling water and intake air temperature were reconstructed using FPGA DAQ boards and a PXI computer. The scanning results showed good agreement with the input signals that were reconstructed. The ECU HILS system operated successfully to drive six fuel injectors, which injected fuel in the same pattern as if they were mounted in the vehicle driven in FTP-75 mode. Also, the fuel injection system developed in this research shows the possibility of application in evaluating the characteristics of fuel injection rate for injectors according to properties of injected fuel with the real driving mode of vehicles.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.3-4
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• 2012

Characteristics of the flow in the incinerator were studied in terms of the cold flow and combustion using multi-staged tangential burner. The design parameters such as deflection angle of main nozzle, and decline angle of assist nozzle habe been changed. The effects of each parameter on burning characteristics have been investigated.

• Journal of Advanced Marine Engineering and Technology
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• 제29권2호
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• pp.154-160
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• 2005

The result of combustion experiment by using the methanol-gasoline blended fuel showed that the supplying pressure appeared the maximum pressure between equivalent rate 1.1 and 1.2. and the evaporation of the fuel has been known to have been greatly influenced by surrounding temperature and the combustion chamber temperature after being injected from the injector And it is confirmed that the rate of evaporation had been suddenly dropped according to the temperature in the combustion chamber though the injected foe) had been fully evaporated Such tendency has visibly appeared when the zone is leaner. and we recognize that the rich fuel supply is needed in the operation of cold operating.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.88.1-88.1
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• 2010

In recent days, the study for the renewable energy is required to supplement traditional energy source. One of the renewable energy of Fuel Cell is classified according to the electrolytes. It is the MCFC (Molten Carbonate Fuel Cell) for this study. One of the equipments of the heat exchangers is important component for efficiency and cost. In MCFC system, several heat exchangers are used according to the application. It is named for the humidifier because it is to preheat the fuel and water so that a reactor will convert some of the incoming fuel to hydrogen. Then, hot side fluid service is used the exhausted gas from the fuel cell and cold side fluid service is the fuel and water. The operation temperature range is about 25~500 Celsius Degree. This heat exchanger has the problems of heat transfer considering to multiphase fluid and phase changing. So it is necessary to analyze the heat transfer characteristics and to propose the reasonable design methodology for the humidifier. In this study, the thermal characteristic for the humidifier is estimated by using commercial tool of heat exchanger design and rating. And this study provides the testing methodology and presents the results for test facility of fabrication and for testing.

• 한국자동차공학회논문집
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• 제9권5호
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• pp.54-61
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• 2001

It is reported that during the cold starting, especially in gasoline engine, the engine response and the effect of HC emission can be improved by prompting atomization and reducing the quantity of fuel adhered to the range of injector tip, inlet port, and inlet valve. The purposes of this study are to promote atomization of fuel before air-fuel mixture in the inlet port. In order to achieve its goal, the glow plug is to evaluate the feasibility of for the early fuel evaporator and the spray behavior characteristics of gasoline, injected on the surface of glow plug with room temperature(2$0^{\circ}C$) and high temperature(25$0^{\circ}C$) is to examine. Particle motion analysis system(PMAS) was used to measure the SMD and the dropsize distribution of impinging spray and free spray. The results of this experiment, evaporation rate of impinging spray was higher than that of free spray, and the higher evaporation rate win, the smaller peak dropsize was. Especially, during early spray SMD of impinging spray was still smaller than that of fee spray.

• 한국응용과학기술학회지
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• 제34권4호
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• pp.962-973
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• 2017

대기오염에 대한 관심은 국내 외에서 점진적으로 상승하고 있으며, 자동차 및 연료 연구자들은 청정(친환경 대체연료) 연료와 연료품질 향상 등을 이용하여 새로운 엔진 설계, 혁신적인 후처리 시스템 등의 연구를 통하여 차량 배기가스 및 온실가스를 감소시키고자 노력하고 있다. 이에 본 연구에서는 각기 다른 차량기술이 적용된 휘발유, 경유, LPG를 연료로 사용하는 7대의 차량을 대상으로 국내 외에서 법적시험모드로 사용되고 있는 도심모드, 고속모드, 급가 감속, 에어컨사용 및 겨울철 특성을 반영한 저온모드에서 온실가스의 배출특성을 확인하고자 하였다. 사용연료에 관계없이 대부분의 온실가스는 저온인 Cold FTP-75 모드에서 가장 안 좋은 결과가 나타나는 경향을 가지고 있다. 각 차량별 온실가스 증가 요인으로는 가솔린 차량인 A차량(2.0 MPI)과 B차량(2.4 GDI)에서는 최고속 및 급가 감속, 에어컨 사용, 저온 조건의 순인데 비해 E차량(1.6 T-GDI)은 에어컨 사용, 최고속 및 급가 감속, 저온 조건의 순이다. G차량(LPLi)은 에어컨 사용, 저온, 최고속 및 급가 감속 조건의 순으로 가솔린 차량과 다른 특성을 가지고 있다. 경유 차량에 있어서는 A차량(2.0 w/o DPF)과 B차량(2.2 w/ DPF)은 최고속 및 급가 감속, 에어컨 사용, 저온 조건의 순이었고, F차량(1.6 w/ DPF)은 저온, 에어컨 사용, 최고속 및 급가 감속 조건의 순으로 확인되었다. 따라서, 각 연료별로 배출가스 저감 기술을 다르게 적용하여야 효과적인 방법이라고 할 수 있겠다.