http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Experimental investigation on evaporation of urea‐water‐solution droplet for SCR applications
Wang, Tae Joong,Baek, Seung Wook,Lee, Seung Yeol,Kang, Dae Hwan,Yeo, Gwon Koo Wiley Subscription Services, Inc., A Wiley Company 2009 AIChE Journal Vol.55 No.12
<P><B>Abstract</B></P><P>The evaporation behavior of urea‐water‐solution (UWS) droplet was investigated for application to urea‐selective catalytic reduction (SCR) systems. A number of experiments were performed with single UWS droplet suspended on the tip of a fine quartz fiber. To cover the temperature range of real‐world diesel exhausts, droplet ambient temperature was regulated from 373 to 873 K using an electrical furnace. As a result of this study, UWS droplet revealed different evaporation characteristics depending on its ambient temperature. At high temperatures, it showed quite complicated behaviors such as bubble formation, distortion, and partial rupture after a linear D<SUP>2</SUP>‐law period. However, as temperature decreases, these phenomena became weak and finally disappeared. Also, droplet diminishment coefficients were extracted from transient evaporation histories for various ambient temperatures, which yields a quantitative evaluation on evaporation characteristics of UWS droplet as well as provides valuable empirical data required for modeling or simulation works on urea‐SCR systems. © 2009 American Institute of Chemical Engineers AIChE J, 2009</P>
이준규(Joon Kyu Lee),이제형(Je-Hyung Lee),여권구(Gwon-Koo Yeo),김문성(Moon-Sung Kim) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
To develop the multiple injection strategy in a HSDI diesel engine, optimization analysis was applied. The optimization analysis has 3 steps. The 1<SUP>st</SUP> step is spray characteristic analysis through the common rail injector modeling with HYDSIM. The 2<SUP>nd</SUP> step is 3-D combustion analysis and verification for the base operating condition with KIVA3Y. The 3<SUP>rd</SUP> step is optimization procedure with KIVA3V and ISIGHT. Above all, the optimization procedure also consists of3 steps. The 1st step is DOE(Design of Experiment), The 2<SUP>nd</SUP> step is Approximation, and the 3<SUP>rd</SUP> step is optimization. All of these procedures were very effective and all results agreed well with the experimental data. Through all of these procedure, optimized multiple injection condition reducing emissions(NOx, Soot) and combustion noise(CNL) without penalty of fuel consumption(BSFC) could be evaluated.
동적유동모사장치를 이용한 PZEV 기준 대응용 배기계의 유동 분포 측정을 위한 실험적 연구
김인수(Insu Kim),명차리(Cha-Lee Myung),박심수(Simsoo Park),인치범(Chi-Bum In),여권구(Gwon koo Yeo) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
As the current and future automobile emission regulations become stringent, the research of exhaust manifold and CCC has been the interesting and remarkable subject. The design of a CCC manifold is a formidable task due to the complexity of the flow distribution caused by the pulsating flows that are emitted by the exhaust ports. Measurement of flow distribution can be done with computational fluid dynamics (CFD). However, such simulations must be verified with selected experimental data. In this study, conventional casting type and stainless steel bending type of a 4-cylinder engine(with 900 cell CCC system) was performed to investigate the flow distribution of exhaust gases. Pressure was measured using simulated dynamic flow bench and 5-hole pitot probe. And then the flow uniformity of bending type exhaust manifold compared with that of the casting type. Based on the experimental data, this study verified exhaust system optimization for the better use of catalytic converter.
상용차용 요소-선택환원촉매 시스템의 탈질성능에 관한 연구
한평현(Pyung Hyun Han),김규홍(Gyu Hong Kim),길정기(Jeong Ki Kil),여권구(Gwon Koo Yeo) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
The effect of various factors on NOx conversion was investigated for urea-SCR, the selective catalytic reduction using urea as reducing agent. Zeolite-based SCR catalysts were tested in the ESC test cycle using a 4L diesel engine, with and without diesel oxidation catalyst. The theoretical maximum NOx conversion was considered based on the SCR kinetics and it was compared with the NOx conversions obtained experimentally on various experimental conditions. NH₃/NOx ratio, NO₂/NOx ratio and reaction temperature are the main factors affecting the DeNOx performance of SCR system. Additionally, the distance between urea dosing point and SCR catalyst significantly influences the performance of SCR catalyst.
한용택(Yong-Taek Han),배귀남(Gwi-Nam Bae),이진하(Jin-Ha Lee),여권구(Gwon-Koo Yeo) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
In this study, a combustion aerosol generator system was designed and developed and several parametric study was performed experimentally. Particle size distributions were measured using a scanning mobility particle sizer(SMPS). An electric furnace was utilized to control the temperature of simulated gas. The particle size distribution and temperature along with the simulated exhaust pipe was measured. There could be several mechanisms for particle movement and generation, and we thought that thermophoresis, nucleation, and condensation could be generated for the behavior of particles in this system. The size distribution of aerosols generated from the combustion aerosol generator was highly dependent on the combustion air, and it was insensitive to other parameters. Particle formation in a tube furnace was observed when the furnace temperature were higher than 450℃. In the simulated exhaust pipe, the particle loss due to thermophoresis was also monitored at the high temperature.