Download CI Engine Emission Control - Engine Combustion - Lecture Notes and more Study notes Sustainability Management in PDF only on Docsity! Objectives_template file:///C|/...%20and%20Settings/iitkrana1/My%20Documents/Google%20Talk%20Received%20Files/engine_combustion/lecture26/26_1.htm[6/15/2012 3:06:10 PM] Module 6:Emission Control for CI Engines Lecture 26:An Overview of CI Engine Emission Control The Lecture Contains: EMISSION CONTROL IN CI ENGINES AN OVERVIEW OF CONTROL OF CI ENGINE EMISSIONS Objectives_template file:///C|/...%20and%20Settings/iitkrana1/My%20Documents/Google%20Talk%20Received%20Files/engine_combustion/lecture26/26_2.htm[6/15/2012 3:06:10 PM] Module 6:Emission Control for CI Engines Lecture 26:An Overview of CI Engine Emission Control AN OVERVIEW OF CONTROL OF CI ENGINE EMISSIONS For emission control in the CI engines, usually called as the diesel engines the following are important; CI engines emits pollutants in solid (soot), liquid (poly aromatic hydrocarbons, fuel and oil components, sulphur acids) as well as those in gaseous (CO, HC, NOx) state. Emissions of nitrogen oxides and particulate matter from diesel engines are of main concern. Emission regulations do have limits for CO and HC as well from the CI engines, but concentration of their emissions is rather small and these have been relatively easy to control through improved engine and fuel system design. NOx - PM trade off (discussed in Module 2) governs selection and optimization of many engine design variables e.g, injection timing, injection pressure, boost pressure etc as change in some engine variables may although causes reduction in NOx but increases PM and vice versa. Engine design changes to reduce NOx emissions many a times result also in higher brake specific fuel consumption (BSFC). This is important as the emissions of the greenhouse gas, CO2 are also to be reduced. The development efforts like for the SI engines have been focused on reduction of engine-out emissions and treatment of the exhaust gases. Improvements in fuel quality also have been made to meet the needs of advanced emission control technology. In CI engines, mixture formation and combustion is heterogeneous and complex in nature. It is governed by;
