Department News
Experimental Studies of Physical and Chemical Phenomena Important During Ignitio
Seminar Date
2004-04-21
Author
임아주
Date
2004-04-21
Views
1729
1. 제 목 :
Experimental Studies of Physical and Chemical Phenomena Important
During Ignition Events
2. 연 사 : Professor M. S. Wooldridge
Department of Mechanical Engineering,
University of Michigan
3. 일 시 : 2004년 5월 4일 화요일 오후 4시
4. 장 소 : 301동 1512호
5. 내 용 :
Auto-ignition of hydrocarbon fuel mixtures is an important topic for developing advanced engine technologies, particularly homogeneous charge compression ignition (HCCI) technologies. HCCI represents a potential major advancement in high-efficiency, low-emission engines. HCCI is lean burning and has no throttling losses, which leads to high efficiencies and low NOx emissions (and potentially low particulate emissions). In addition, the HCCI engine can have much higher partial load efficiency than a spark ignition (SI) engine. Although HCCI engines have been demonstrated to function well at some operating conditions, obstacles have been encountered at controlling the autoignition event over a large range of engine load and speed conditions, e.g. at low-load conditions, cold-starts, and during transients between operating conditions. HCCI combustion is achieved by controlling the temperature, composition and pressure of the fuel and air mixture so that it spontaneously ignites at or close to top dead center. Consequently, the control system is fundamentally more challenging than using a spark plug or fuel injector to determine ignition timing. It is generally well accepted that the local reaction kinetics are the most important processes affecting HCCI combustion. Therefore, an extensive understanding of HCCI reaction chemistry is required to address technological barriers and develop valuable control strategies for HCCI engines.
In this work, the physical and chemical phenomena important during autoignition events have been extensively characterized in the well-controlled environment provided by the University of Michigan rapid compression facility (RCF). The RCF experiments have been used to characterize the ignition delay times as a function of pressure, temperature, equivalence ratio, exhaust gas residuals and oxygen concentrations. Also as part of this work, breakthrough imaging clearly delineating the lean flammability limits has been obtained.
6. 문 의 : 기계항공공학부 민경덕 교수 (Tel:880-1661)
Experimental Studies of Physical and Chemical Phenomena Important
During Ignition Events
2. 연 사 : Professor M. S. Wooldridge
Department of Mechanical Engineering,
University of Michigan
3. 일 시 : 2004년 5월 4일 화요일 오후 4시
4. 장 소 : 301동 1512호
5. 내 용 :
Auto-ignition of hydrocarbon fuel mixtures is an important topic for developing advanced engine technologies, particularly homogeneous charge compression ignition (HCCI) technologies. HCCI represents a potential major advancement in high-efficiency, low-emission engines. HCCI is lean burning and has no throttling losses, which leads to high efficiencies and low NOx emissions (and potentially low particulate emissions). In addition, the HCCI engine can have much higher partial load efficiency than a spark ignition (SI) engine. Although HCCI engines have been demonstrated to function well at some operating conditions, obstacles have been encountered at controlling the autoignition event over a large range of engine load and speed conditions, e.g. at low-load conditions, cold-starts, and during transients between operating conditions. HCCI combustion is achieved by controlling the temperature, composition and pressure of the fuel and air mixture so that it spontaneously ignites at or close to top dead center. Consequently, the control system is fundamentally more challenging than using a spark plug or fuel injector to determine ignition timing. It is generally well accepted that the local reaction kinetics are the most important processes affecting HCCI combustion. Therefore, an extensive understanding of HCCI reaction chemistry is required to address technological barriers and develop valuable control strategies for HCCI engines.
In this work, the physical and chemical phenomena important during autoignition events have been extensively characterized in the well-controlled environment provided by the University of Michigan rapid compression facility (RCF). The RCF experiments have been used to characterize the ignition delay times as a function of pressure, temperature, equivalence ratio, exhaust gas residuals and oxygen concentrations. Also as part of this work, breakthrough imaging clearly delineating the lean flammability limits has been obtained.
6. 문 의 : 기계항공공학부 민경덕 교수 (Tel:880-1661)
