• Title/Summary/Keyword: aftertreatment

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The Experimental Research of LNT for 3L-DME Engine (3리터급 DME 엔진용 LNT 후처리 장치 연구)

  • Jang, Jinyoung;Lee, Youngjae;Pyo, Youngduk;Cho, Chongpyo;Woo, Youngmin
    • Transactions of the Korean Society of Automotive Engineers
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    • v.21 no.6
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    • pp.117-122
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    • 2013
  • This study is aimed to develop LNT(Lean NOx Trap) aftertreatment system for DME engine. Modified DME engine, which was changed from diesel to current DME engine, is used for this research and is equipped with common rail type injector and fuel supplying system. LNT system has reductant injector. DME is also used as reduction agent. For this research, reduction agent injection time width and interval were varied. And also, swirler was used to improve homogeneity of reducing agent in exhaust pipe. The reduction rate of NOx by LNT was increased by longer injection width, short interval and swirler. The maximum diminution of NOx by LNT was over 85%.

Unified Modeling and Performance Prediction of Diesel $NO_x$ and PM Reduction by DOC-DPF-SCR System (DOC-DPF-SCR 시스템에 의한 디젤 배기 내 $NO_x$, 입자상 물질 저감 과정의 일관 모델링 및 성능 예측)

  • Jung, Seung-Chai;Yoon, Woong-Sup
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.4
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    • pp.110-119
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    • 2008
  • Computer methods with simplified mathematical models in conjunction with empirical model parameters can be efficiently practiced into an optimization of a diesel aftertreatment system. Components of prime interests are diesel particulate filter, diesel oxidation catalyst and de-$NO_x$ catalytic converter. de-$NO_x$, de-PM, and de-HC processes in each part are individually modeled, formulated and then combined into an integrated analysis procedure for a unified simulation of the diesel emission aftertreatment. The model is empirically tuned and validated with comprehensive engine and laboratory data. The effects of emission species and space velocity on the $NO_x$ and soot reductions are parametrically investigated. A lowered $NO_2/NO_x$ ratio due to PM oxidation in DPF contributes to promote the $NO_x$ reduction by SCR at intermediate gas temperatures. $NO_x$ reduction is inert to the PM oxidation at high temperatures. Rate of PM trapping strongly depends on temperature and $NO_x$ concentration.

Dyeing Properties and Aftertreatment of UMF Nylon 6 Nonwoven Fabric (초극세 나일론 부직포의 염색성 및 후처리)

  • 오준석;정동석;이문철
    • Textile Coloration and Finishing
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    • v.12 no.6
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    • pp.344-352
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    • 2000
  • Two kinds of nylon 6 fabrics with different fiber denier, such as ultramicro fiber(UMF) nonwoven fabric(monodenier 0.05d) and regular fabric(monodenier 2.92d) are dyed with C.I. Acid Red 18(leveling type) and C.I. Acid Blue 113(milling type). Dyeing rates and adsorption isotherms are measured at $60^\circ{C}$, pH 5.0 and at liquor ratio of 1 : 250. To investigate the effect of fixing agents (Matexil FA-SNX, Monorex-RD and Tinofix-ECO) on UMF nylon 6 nonwoven fabric, dyeing is carried out at 3~10% owf with 1 : 2 metal-complex acid dyes, such as Kayalax Navy R(unsulphonated type), Lanasyn Blue S-BL(monosulphonated type) and Kayakalan Black BGL(disulphonated type). The dyeing rate of UMF nylon 6 is faster than that of regular nylon 6. From the results of absorption isotherms, the regular nylon 6 has higher saturation value of Acid Red 18 compared with UMF nylon 6, whereas UMF nylon 6 has higher saturation value of the acid Blue 113. From the absorption isotherms of both acid dyes, the regular nylon 6 has higher saturation value of Acid Red 18, whereas UMF nylon 6 has higher saturation value of the acid Blue 113. The wash fastnesses of UMF nylon 6 increases in the order of metal-complek dye containing nonsulphonated group > monosulphonated group>disulphonated group. Aftertreatment of UMF nylon 6 dyed with unsulponated and monosulphonated dyes improves wash fastness upto grade 1.5, where as that of UMF nylon 6 dyes with disulphonated dye does not improve wash fastness.

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A Study of Aging of Oxygen Sensor (II) (산소센서의 열환에 관한 연구 (II))

  • 손건석;윤승원;고성혁;이귀영
    • Transactions of the Korean Society of Automotive Engineers
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    • v.9 no.1
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    • pp.1-7
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    • 2001
  • Oxygen sensor taken from the aftertreatment systems of 4 vehicles which had been aged in domestic field examined for aging effects on emissions using a idel engine bench. also the artificial sensor signal generated by function generator was supplied to ECU, instead of oxygen sensor to simulate aging effects of oxygen sensor. This study shows that reduction of amplitude, deformation and shift of mean value of aged sensors seriously affect on the engine out emissions and the performance of TWC.

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Diesel Particulate Reduction Efficiency by Diesel Aftertreatment equipments - Concentrate on the Particle Size Distribution - (경유 후처리장치에 의한 입자상물질 저감효과 - 입경분포를 중심으로 -)

  • 정일록;엄명도;류정호;이규원
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.248-249
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    • 1999
  • 지구온난화의 주요 주범인 $CO_2$의 감축을 위해 자동차 연비 및 배출허용기준등을 전 세계적으로 강화하고 있으며 이에따라 선진국에서는 Super Car 및 3L Car Project등을 통해 초저연비자동차 개발을 추진하고 있다. 이런 추세에 따라 압축비가 높아 연소효율이 좋고 연표경제성이 가솔린엔진보다 우수한 경유엔진은 $CO_2$ 배출이 적어 향후 그 보급이 더욱 확대될 것으로 기대되고 있다.(중략)

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A Conversion Rate Prediction Study of Exhaust Gas by Catalyst Simulation in Heavy Duty Natural Gas Vehicle (대형천연가스차량에서 촉매시뮬레이션에 의한 배출가스의 변환율 예측 연구)

  • 한영출;오용석;강호인
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.3
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    • pp.257-264
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    • 2000
  • An aftertreatment device which reduce exhaust gas of natural gas vehicle(NGV), NGV catalyst has important meaning as to reduce the exhaust emission. In this study, the characteristics of NGV catalyst were investigated and the effect parameters of NGV catalyst were analyzed and were predicted by changing the various parameters such as temperature, and gas concentration. The conversion efficiency of NGV catalyst converter was also predicted by Pd-loading, mass flow rate and gas composition.

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A Study of Aging of Oxygen Sensor (1) (산소센서의 열화에 관한 연구(1))

  • 손건석;윤승원;이귀영
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.1
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    • pp.85-91
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    • 2000
  • Oxygen sensors taken from the aftertreatment systems of 4 vehicles which had been aged in domestic filed were examined for aging pattern using a idle engine bench. The sensors were then cut into each layers along their components and characterized for poisoning, surface area and morphology. This study shows that amplitude and mean value of aged sensors are seriously affected by high temperature and oil components of exhaust gas.

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