• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.5912-5918
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• 2014

Owing to highly developed industries and the use of fossil fuels, environmental problems becoming becoming pressing issues globally. Therefore, a study of automobile exhaust is urgently needed. Generally, air is sucked into the engine through the intake manifold. The aims of this study were to reduce the exhaust from used cars and increase the output by removing carbon deposits, which are considered a reason for the increasing exhaust and reduction of output, and the reduction of exhaust, variation of output and stability of idle speed were analyzed. The formation of carbon deposits within the suction manifold was investigated through a test device (KD147). In the intake manifold, the exhaust cleaning effect was confirmed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.5980-5987
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• 2014

As a response to exhaust gas regulations, the electronic control system was applied to the diesel engine. The injected fuel mass and injection timing are accurately controlled using it, and the fuel efficiency and the engine output are significantly increased. In addition, the noise and the vibration of vehicles are decreased. To maintain the optimal performance of an electronic control diesel engine, it is important to control the fuel injection pressure accurately using the fuel pressure regulator. When the fuel pressure regulator is not worked normally, the failure phenomena (starting failure, staring delay, accelerated failure, engine mismatch et al.) occurred because the fuel pressure is not stabilized and controlled accurately. In this study, the effects on a fuel pressure, return fuel mass flow, and engine rotating speed according to the control rate of fuel pressure regulator were investigated to analyze the performance variation under the failure conditions of a fuel pressure regulator. As a result, when the control rate of a fuel pressure regulator decreased by 4%~6% compared to that of the standard condition, the variation of engine rotating speed and return fuel flow were increased greatly, and the abnormal condition occurred. In addition, it is possible to diagnose the failure of a fuel pressure regulator by monitoring these conditions.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.11-18
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• 1993

대기오염물질이 식물에 미치는 영향에 대한 기록은 1920년대부터 나타난다. 1924년 대기오염물질의 피해로 영국 런던의 Kew식물원 일부를 Kent지방으로 이동하였거나 1925년 Canada의 한 제련소에서 배출된 유독오염물질이 미국에까지 영향을 미쳐 수목, 농작물에 피해를 주어 국제적인 문제가 된 사실 등은 수목에 대한 대기오염물질의 피해 심각성을 보여 주는 사례이다(임경빈 등, 1979a, 1979b). 우리나라에서는 1930년이후 흥남질소비료공장에서 배출된 매연물질이 주위 30리까지의 경작지에 피해를 끼쳤다는 사실이 최초로 기록되어 있다.(김태욱, 1976).

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.165-166
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• 2000

대기 중으로 배출되는 분진, 자동차에서 배출되는 매연 등 대기오염의 주요원인인 미세입자의 제거를 위한 방법은 그 적용범위가 제거대상 분진의 크기 및 물리적 특성에 따라 여러 가지로 나누어진다. 분진의 이동은 각각의 부유조건 및 분진의 크기, 그리고 분진의 물리적 특성에 따라 특정한 힘의 지배에 의한다. 일반적으로 산업체에서 발생되는 대용량의 미소분진의 제어는 관성력과 중력 그리고 정전기력을 이용하는 경우가 대부분이다. (중략)

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.267-267
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• 2017

• Journal of Biosystems Engineering
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• v.25 no.6
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• pp.471-480
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• 2000

대체연료로서 바이오 연료의 디젤엔진에의 적합성을 파악하기 위하여 경유, 가온 미강유, 초음파 적용 가온 미강유, 미강유 메틸 에스테르, 폐식용유, 초음파 적용 폐식용유, 폐식용유 메틸 에스테를 14kW 예연소실식 디젤 엔진의 연료로 사용하여 그 성능과 배기배출물을 측정하였다. 시험에 사용한 바이오 연료들에 의해 엔진 분사 펌프의 조정이나 다른 부품의 개조를 하지 않고도 단기간 전부하 상태로 1,600~2,800 rpm 의 범위에서 엔진은 정상적으로작동하였다. 바이오 연료를 사용하였을 경우 전반적으로 엔진성능과 배기 배출물 특성에 있어서 경유를 사용하였을 경우와 비견할만 하였으며 특히 매우 낮은 농도의 $SO_2$와 매연을 배출하였다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.8
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• pp.755-760
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• 2010

In this study, we mainly focused on the PM (Particulate Matter) emission characteristics of a diesel engine. To analyze particle behavior in the tail-pipe, particle emission was measured on the engine-out (downstream of turbocharger), each upstream and downstream both of DOC (Diesel Oxidation Catalyst) and DPF (Diesel Particulate Filter). Moreover, particle emission contours on each sampling point were constructed. The reduction efficiency of particle number concentration and mass through the DOC and DPF was studied. Parameters such as EGR (Exhaust Gas Recirculation) and the main injection timing were varied in part load conditions and evaluated using the engine-out emissions. The DMS500 (Differential Mobility Spectrometer) was used as a particle measurement instrument that can measure particle concentrations from 5 nm to 1000 nm. Nano-particles of sizes less than 30 nm were reduced by oxidation or coagulated with solid particles in the tail-pipe and DOC. The DPF has a very high filtration efficiency over all operating conditions except during natural regeneration of DPF.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.9
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• pp.870-875
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• 2015

Diesel engines are widely used due to superior power and fuel consumption, however there are many challenges in exhaust gas management. Exhaust gas recirculation (EGR) is the most effective technique for reducing mono-nitrogen oxide (NOx) emissions in a diesel engine, in comparison with other catalytic technologies. In addition, the technology has a number of advantages in terms of economic efficiency and implementation. In this study, the effects on the power and exhaust characteristics of diesel engines equipped with EGR systems were investigated. It was found that as the EGR rate increased, horsepower expressed as IHP and BHP decreased. The net effect of the application of EGR was measured at various engine speeds. EGR technology caused decreases in BHP of around 9% during low engine speed and 3.5% during high engine speed. Additionally, NOx emissions reduced as the EGR rate increased, and increased as engine speed increased. However, smoke emissions increased as the EGR rate increased, and decreased as engine speed increased. The optimum operating conditions and ERG rate to simultaneously achieve minimum NOx and smoke emissions were investigate. It was found that as the EGR rate increased, optimal operating speed for minimal NOx and smoke also increased. Keywords: Diesel engine, Exhaust gas recirculation, Power perfomance, Emission characteristics, NOx, Smoke

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.83-87
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• 2008

We have a lot of interest in alternative fuels to provide energy independence from oil producing country and to reduce exhaust emissions for air pollution prevention. Biodiesel, which can be generated from natural renewable sources such as new or used vegetable oils or animal fats, may be used as fuel without change of engine structure in diesel engine of compression ignition engine. In this paper, the test results on specific fuel consumption and exhaust emissions of neat diesel oil and biodiesel blends(10 vol.% biodiesel and 20 vol.% biodiesel) were presented using four stroke, direct injection diesel engine. Especially this biodisel was produced from rape oil at our laboratory by ourselves. This study showed that specific fuel consumption and NOx emission were slightly increased, on the other hand CO emission and Soot were tolerably decreased more in the case of biodiesel blends than neat diesel oil.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.19-20
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• 2006

The emission of particulate matter from marine diesel engines is already restricted by regional regulations in some countries, and IMO has been preparing the regulation for particulate matter from 53rd MEPC. But confusingly, the gravimetric PM measurement methods and procedures are not established clearly yet. On the other hand, smoke measurement method is set clearly, and it can also indicate PM, though it is not direct gravimetric method. As the preparing step for regulations about PM, we measured the smote density of exhaust emission from the marine four-stroke diesel engines operated in constant speed and various load steps on the test-bed, using the filter-type smoke measuring instrument. As a result, we understood the omission characteristics of smoke from the engines. Additionally, to obtain the objective reliability of our measurement data, we carried out experimental studies about various measuring parameters that could affect the smoke density.