Study on Di-Ci Diesel Engine Characteristics by Exhaust Gas Recirculation Using Waste Cooking Methyl Ester

Abstract

Fossil fuels are limited in nature. Fuel consumption rate is increases and there will be the need of alternate fuels in future. Replacing biodiesel as a fuel in the place of standard fuel to study the characteristics of performance, combustion and emissions of the DI-CI diesel engine. DI-CI engine with biodiesel all the characteristics are investigated. The results of engine characteristics with biodiesel were compared with standard baseline petroleum diesel. Fuel in any engine burnt with air. Air is a mixture of gases and it contains approximately 78% nitrogen and 21% oxygen. Some of the oxygen is used to burn the fuel during the combustion process and the rest is supposed to just pass through unreacted. But when the peak temperatures are high enough for long periods of time, the nitrogen and oxygen combine to form a class of compounds called nitrogen oxides, collectively referred to as NO_x. These compounds are one of the chief constituents of smog, which have an adverse effect on ecological systems. NOx emissions can be reduced by lowering the cylinder temperatures. This is done by recirculating some exhaust gas and mixing it into the engine inlet air. This process is known as Exhaust Gas Recirculation (EGR). The objective of Exhaust Gas Recirculation (EGR) is to reduce the amount of NO_x produced. The EGR valve recirculates gases into the intake stream. Exhaust gases have already combusted, so they do not burn again when they are recirculated. These gases displace some of the normal intake charge. This chemically slows and cools the combustion process by several hundred degrees thus reducing NO_x formation.