• 한국자동차공학회논문집
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• 제16권5호
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• pp.84-91
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• 2008

Due to increasing need for better emission characteristics and lower fuel consumption rate in automotive engines, alternative fuels are drawing more attentions recently. The GTL (gas to liquid) is the one of most favored candidates. In this study, emission characteristics are compared between diesel and GTL fuel in commercial 2.0 liter diesel engine and vehicle with CRDi(Common Rail Direct injection) system. The effects of injection timings on emission and fuel consumption rate are compared at various engine speeds and loads. Noticeable reduction in HC, CO and PM emissions are observed due to higher cetane number and low sulfur and aromatic contents in GTL. On the trade-off curve of NOx and PM(Particulate matter) GTL showed much more benefits than diesel, where about 30% of PM mass decreased at the same operating conditions. On CVS 75 mode test in vehicle, GTL showed an excellent emission enhancement, in which 50% of HC, 21% of PM, and 12% of NOx engine-out emissions are decreased compared to ULSD(Ultra low sulfur diesel) fuel.

• 한국산학기술학회논문지
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• 제19권6호
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• pp.689-695
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• 2018

본 연구는 배기가스 기준을 만족하기 위해 차량에 장착된 배기가스 후처리 장치(DPF)의 재생제어 방안에 대한 것이다. DPF는 배기가스에 포함된 입자상 물질(PM)을 포집하기 위한 필터로 DPF에 포집된 PM은 일정 조건에 이르렀을 때 고온의 배기가스로 연소시킨다. 이러한 과정을 재생(Regeneration)이라 하는데 DPF의 정상적인 성능을 위한 필수 과정이다. 재생이 잘 되지 않을 경우, 차량의 성능저하와 심한 경우 차량의 화재로도 이어질 수 있다. DPF의 재생은 제어로직에 의해 수행되는데 재생제어 로직이 차량의 운용특성을 제대로 반영하지 못한 경우 DPF 재생이 이루어지지 않을 수 있다. 그렇기 때문에 전술차량의 운용특성을 파악하여 DPF가 정상적으로 재생될 수 있도록 하는 것이 매우 중요하다. 본 연구에서는 전술차량의 운용 특성과 DPF의 특성을 분석하여 이에 맞는 DPF의 재생 제어 로직을 추가하고자 한다. 더불어 추가된 재생 제어 로직에 따른 운용 시 발생될 수 있는 추가적인 문제점까지 동시에 개선하고자 한다.

• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.231-236
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• 2003

HCCI(Homogeneous Charge Compression Ignition) combustion is an advanced combustion process explained as a homogeneously premixed charge of a fuel where air is admitted into the cylinder and compression ignited. It has possibility to reduce NOx by spontaneous auto-ignition at multiple points that allows very lean combustion resulting in low combustion temperatures. Particulate matters (PM) could be also reduced by the homogeneous combustion and no fuel-rich zones. Injection timing is extremely advanced to achieve homogeneous charge where a diesel fuel could not be vaporized sufficiently due to low pressure and low temperature condition. Also the over-penetration could be a severe problem. The small injection angle and multi-hole injectors were applied to solve these problems. Dimethyl ether (DME) as an altenative fuel was also applied to relive the bad vaporization problem associated with early injection of diesel fuel. Neat DME has a very high cetane rating and high vapor pressure. Contained oxygen reduces soot during the combustion. Experimental result shows DME can be easily operated in an HCCI engine. PM shows almost zero value and NOx is reduced more than 90% compared to direct-injection diesel engine operating mode but problem of early ignition needs more investigation.

• 한국분무공학회지
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• 제18권1호
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• pp.21-26
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• 2013

Diesel low temperature combustion (LTC) is the concept where fuel is burned at a low temperature oxidation regime so that $NO_x$ and particulate matters (PM) can simultaneously be reduced. There are two ways to realize low temperature combustion in compression ignition engines. One is to supply a large amount of EGR gas combined with advanced fuel injection timing. The other is to use a moderate level of EGR with fuel injection at near TDC which is generally called Modulated kinetics (MK) method. In this study, the effects of fuel injection pressure on performance and emissions of a single cylinder engine were evaluated using the latter approach. The engine test results show that MK operations were successfully achieved over a range of with 950 to 1050 bar in injection pressure with 16% $O_2$ concentration, and $NO_x$ and PM were significantly suppressed at the same time. In addition, with an increase in fuel injection pressure, the levels of smoke, THC and CO were decreased while $NO_x$ emissions were increased. Moreover, as fuel injection timing retarded to TDC, more THC and CO emissions were generated, but smoke and $NO_x$ were decreased.

• 한국공작기계학회논문집
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• 제12권6호
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• pp.104-111
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• 2003

In order to collect the engine performance data and determine optimum engine conditions, engine performance test based on interface unit were tested This paper was carried out that engine' performance was developed using interface unit between personal computer and diesel engine. The results of the study are summarized as follows: Interface unit was developed. By using PAL, simulation was carried in order to logic's inspection. From this tea NO$_{x}$ were decreased, otherwise PM were increased. By using EGR system PM were increased by twice in the high load ranges, it was not seen to come into effect in the low load ranges. This system was tested D-l3 mode, the results were decreased more than 50% in the NO$_{x}$ emission.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1558-1563
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• 2007

The air pollution by the diesel locomotives has become serious environmental concern because the emission gases are exhausted without any further treatment. Recently, the public interest on the air pollutants emission reduction technology is increasing due to the establishment of 'Metropolitan Air Quality Preservative Law' and the regulation of local governments on the urban air quality. In this study, we measured the concentration of particulate matters and gaseous pollutants by using a scanning mobility particle sizer, a dust spectrometer, and a stack sampler upon various engine load condition. The results show that the amount of emitted air pollutants increased upon the increase of engine power. The development of new technology to reduce the air pollutants emission is urgently required.

• 자동차안전학회지
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• 제6권1호
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• pp.33-40
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• 2014

In this study the cylinder liner deformation which is one of the most influencing factors in a diesel engine oil consumption was performed by the finite element analysis on the basic designed structure consisting of the cylinder block, head and liners under the conditions of assembly, thermal and gas loads. Compared with a large number of other cylinder blocks showing remarkable harmonic orders of the liner distortion, results are excellent. Namely. the higher harmonic order amplitudes of the radial liner deformation amount to 1 ~ 2㎛ maximally. The main reason lies in the relatively large wall thickness of the liner which amounts to 8.2% of the bore diameter. Besides, a very stiff and symmetrical cylinder block design in combination with a bolt force introduction approximately 1.5mm below the block top deck have a further share on these results. Therefore excellent low oil consumption can be expected.

• 동력기계공학회지
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• 제10권2호
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• pp.11-15
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• 2006

The increasing numbers of automobiles keep causing air-pollution problems worse than ever. Nowadays, research on catalyst converter and filter trap as a modern technology is very active because PM is designated as a major cancer material and stringent regulations on this are necessary and required. This research emphasized on the development of Continuously Regenerating DPF technology which was the best particulate matters removing technology of current existing technology because of its superior comparability and high applicability. This experimental study has been conducted with equipped and unequipped a Continuously Regenerating DPF ona displacement 7,000cc diesel engine and compared in terms of engine performance and emission. To measure the emission, D-13 mode is applied and measured quantities of the exhaust gases, particularly in CO, HC, PM, and NOx. Therefore, this research is focused on engine performance and characteristics on exhaust emissions with the application of a Continuously Regenerating DPF in a heavy-duty diesel vehicle.

• 한국자동차공학회논문집
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• 제14권2호
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• pp.145-150
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• 2006

Recently emission regulation on diesel vehicles is getting stringent and research on aftertreatment technology such as DPF and DOC has been carried out actively. Even though PM(Particulate matters) reduction efficiency in DOC is relatively low but the structure is simpler and very effective in the reduction of gas materials and unregulated materials. Therefore it has been applied to smaller diesel vehicles. The aims of this research is to investigate the emission reduction characteristics of DOC; DOC performance of regulated and unregulated material emission reduction. It results a Pt based catalyst demonstrated higher emission reduction efficiency than a Pt-V based catalyst in CVS-75 mode, and also the reduction efficiency of unidentified material was excellent.

• 생명과학회지
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• 제17권3호통권83호
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• pp.396-401
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• 2007

천식이 유발된 Balb/c마우스와 동일한 조건의 IL-10 KO 마우스에 천식의 원인으로 알려진 DEP와 지하철역내에서 채집한 PM (10 ${\mu}g/m^3$)을 inhalation chamber,에 넣고 하루 4시간씩 흡입시킨 후 시료들을 채취하여 ICAM-1, VCAM-1의발현을 살펴 천식증상의 악화에 DEP와 PM이 어데한 영향을 미치는지 확인하였다. 본 실험의 결과 천식이 유발된 일반 Balb/c 마우스에 있어서는 DEP와 PM의 노출에 의하여 ICAM-1 및 VCAM-1의 발현이 세기관지 주위 조직들에서 미약하게 증가하였다. 그러나 IL-10 KO 마우스의 경우 DEP와 PM을 노출시켰을 때 ICAM-1 및 VCAM-1의 발현이 아주 강하게 증가하였다. 따라서, 본 결과는 IL-10에 대한 항체요법이 천식증상의 완화에 쓰일 수 있는 가능성을 암시하며, 한편 자동차 배기가스와 지하철 미세분진의 발생을 예방할 경우 천식과 관련한 세기관지의 염증을 완화시킬 수 있음을 간접적으로 증명한 것이라 할 수 있다.