http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
가솔린기관의 냉시동시 촉매 가열 촉진을 위한 점화시기 영향에 대한 실험적 연구
권영웅,함성훈 한국기계기술학회 2011 한국기계기술학회지 Vol.13 No.4
On cold start operation of an SI engine, a catalyst shows poor performance before it reaches activation temperature. Therefore, fast warmup of the catalyst is very crucial to reduce harmful emissions. In this study, an appropriate control strategy is investigated to increase exhaust gas temperature through changes of spark timing. Combustion stability is also considered at the same time. Exhaust gas temperature and pressure of combustion chamber are measured to investigate the effects of spark timings on cold start and idle performance. Experiments showed that retarded spark timing promotes the combustion at the end of expansion stroke and increases exhaust gas temperature during cold start.
조용석,김득상 국민대학교 생산기술연구소 2002 공학기술논문집 Vol.25 No.-
UEGI (Unburned Exhaust Gas Ignition) is expected to help faster warm up of a close-coupled catalytic converter (CCC) by igniting the unburned exhaust mixture using two glow plugs installed in the upstream of the catalyst. In this study, a control module and an algorithm for the UEGI technology was developed. It changes I/O signals from the ECU, and controls ignition signals, glow plug on/off signals, and cooling water temperature signals to modify A/F ratios during cold start of the test engine. The control module is also designed to be readily applicable to a conventional vehicle, therefore, its repeatability, stability of UEGI flame, precision of light-off time and performance characteristics were tested and analyzed on an engine test bench. In addition, both the UEGI system and a hydrocarbon adsorber were applied to the exhaust system for more effective reduction of HC emission during the cold start period. Experimental results show that the CCC reaches the light-off temperature faster compared with the Baseline exhaust system, and HC and CO emissions are reduced significantly during the cold start. The UEGI control module proved its effectiveness in precise control of the UEGI system.
김성수 신라대학교 자연과학연구소 2003 自然科學論文集 Vol.12 No.-
The effects of temperatures of catalytic converter, intake temperatures and fuel skip injections on engine-out HC emissions were investigated during cold and hot start. The tests were conducted according to engine cooling temperatures which were controlled by simulated coolant temperatures of cold and hot start, on a 1.5L, 4-cylinder, 16valve, multipoint-port-fuel-injection gasoline engine. Real time engine-out HC emissions were measured at a exhaust port and cylinder head using Fast Response Flame Ionization Detector (FRFID). Unburned hydrocarbons emitted at the cold coolant temperature were much higher than those of the hot coolant temperatures. And temperatures of catalytic converter and applications of fuel skip injections which can be controlled with coolant temperatures provide the high potential for start-up engine-out HC emissions reduction.
김득상(D. S. Kim),강봉균(B. G. Kang),김성철(S. C. Kim),이상진(S. J. Lee),양창석(C.S. Yang),조용석(Y. S. Cho) 대한기계학회 2001 대한기계학회 춘추학술대회 Vol.2001 No.9
UEGI (Unburned Exhaust Gas Ignition) is expected to help faster warm up of a close-coupled catalytic converter (CCC) by igniting the unburned exhaust mixture using two glow plugs installed in the upstream of the catalyst. In this study, a control module and an algorithm for the UEGI technology was developed. It changes I/O signals from the ECU, and controls ignition signals, glow plug on/off signals, and cooling water temperature signals to modify A/F ratios during cold start of the test engine. The control module is also designed to be readily applicable to a conventional vehicle, therefore, its repeatability, stability of UEGI flame, precision of light-off time and performance characteristics were tested and analyzed on an engine test bench. In addition, both the UEGI system and a hydrocarbon adsorber were applied to the exhaust system for more effective reduction of HC emission during the cold start period. Experimental results show that the CCC reaches the light-off temperature faster compared with the Baseline exhaust system, and HC and CO emissions are reduced significantly during the cold start. The UEGI control module proved its effectiveness in precise control of the UEGI system.
연료전지 차량의 냉시동성 개선을 위한 금속 분리판 표면의 바나듐 산화물 박막 제조 및 특성 분석에 관한 연구
정혜미(Hye-Mi Jung),노정훈(Jung-Hun Noh),임세준(Se-Joon Im),이종현(Jong Hyun Lee),안병기(Byung Ki Ahn),엄석기(Sukkee Um) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11
Cold-start capability of polymer electrolyte fuel cells is a major technical challenge for fuel cell vehicles in a subzero environment. In this study, vanadium oxide thin films deposited onto the flat surface of 316L stainless steel bipolar plates have been synthesized to investigate applicability as an efficient self-heating source for accelerating fuel cell stack temperature rise during subzero startup. The solid thin films have been prepared by the dip-coating technique via the hydrolytic sol-gel route and then the chemical compositions and microstructures of the films were analyzed by X-ray diffraction, X-ray fluorescence spectroscopy, and field emission scanning electron microscopy. In addition, it was carefully measured electrical resistance hysteresis loop and local surface temperature of the thin films over a temperature range from -20℃ to 80℃ by a fourterminal technique. It was found that thermal dissipation rate of the vanadium oxide thin films partially satisfy roughly 50% saving of the substantial amount of energy required for ice melting at startup temperature of - 20℃ and current density of 0.1 A/㎠.
미연 배기가스 점화기술을 적용한 차량의 배기저감 성능에 관한 연구
조용석 국민대학교 생산기술연구소 2003 공학기술논문집 Vol.26 No.-
UEGI(Unburned Exhaust Gas Ignition) is an alternative method for fast light-off of a catalytic converter. It ignites unburned exhaust mixture using two glow plugs installed in the upstream of the close-coupled catalysts(CCC). In addition, a hydrocarbon adsorber was applied to the UEGI system, for more effective reduction of HC emission. Engine bench tests show that the CCC reaches the light-off temperature faster compared with the baseline exhaust system and HC and CO emissions are reduced significantly during the cold start. From vehicle tests it was observed that HC emission was reduced effectively, even the catalysts were aged. It is expected to develop a solution kit applicable to a new vehicle or used one, to meet the stringent emission regulation.
맥동유동을 이용한 연료전지의 퍼지성능 향상에 관한 연구
장지용(Ji Yong Jang),최종원(Jong Won Choi),김성일(Sung Il Kim),김민수(Min Soo Kim) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11
This paper describes how residual water uptaken in the membrane is removed more effectively by a pulsating flow than by a constant flow. Generally, residual water in the membrane should be removed mostly in a subzero condition since ice formed in that condition can plug pores of the catalyst layer so that fuel cannot be supplied properly. Therefore, air is usually driven into fuel cells for drying the membrane and helping a proper cold start. However, it is predicted that too much power should be consumed by a blower if it takes long time to dry out the membrane. In this study, purge with pulsating flow before shutting down is investigated experimentally for making the purge duration shorter. According to the results, purge time is shorter as the pulsation frequency is higher, which is saved up to 45% for the frequency of 12 ㎐ than that without pulsation due to the increasing mass transport between the channel and the membrane.
정상 및 유사휘발유의 환경조건별 배출가스 및 연비에 미치는 영향에 대한 연구
김정환(Jeonghwan Kim),인정민(Jungmin In),박종배(Jongbae Pak),이민호(Minho Lee),김재권(Jaigueon Kim),정충섭(Choong Sup Jung) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11
As the interest on the air pollution is gradually rising up at home and abroad, automotive and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean fuels and fuel quality improvement. However, a study that the fuel quality affect on exhaust emission from vehicle. This research shows that the irregular gasoline fuel had some problem that cause of ambient pollution, power decreasing, fallen to safety and trouble of engine. At the cold-start operating condition, the irregular gasoline fuel is happened to the unregulated exhaust emissions. Also, based on these problem, this paper discusses the influence of gasoline fuel quality on automotive exhaust emissions.
복합재료 샌드위치 엔드플레이트의 연료전지 냉시동성 향상에 미치는 효과
서정도,고재준,안병기,유하나,이대길 한국수소및신에너지학회 2011 한국수소 및 신에너지학회논문집 Vol.22 No.6
The cold start problem is one of major obstacles to overcome for the commercialization of fuel cell vehicles. However, the cold start characteristics of fuel cell systems are very complicated since various phenomena, i.e. ice-blocking, electro-chemical reactions, heat transfer, and defrosting of BOP components, are involved in them. This paper presents a framework to approach the problem at a full stack scale using Axiomatic Design (AD). It was characterized in terms of Functional Requirements (FRs) and Design Parameters (DPs)while their relations were established in a design matrix. Considering the design matrix, the endplates should have low thermal conductivity and capacity without increase in weight or decrease in structural stiffness. Consequently, composite sandwich endplates were proposed and examined both through finite element analyses and experiments simulating cold start conditions. From the examinations, it was found that the composite sandwich endplates significantly contributed to improving the cold start characteristics of PEMFC.