Review on Effect of Exhaust Gas Recirculation (EGR) on Performance of Compression Ignition (CI) Engine and Homogeneous Charge Compression Ignition (HCCI) Engine

Abstract

Energy conservation is a trending topic in the world. But only saving energy is not the primary aim, there is a need for clean and efficient source of energy to reduce the pollution. Compression ignition engine is the preferred prime movers due to excellent drivability and higher thermal efficiency. Even though it has many advantages, it also has major drawbacks as it produces higher level of NOx and smoke emissions which cause severe health issues to the living creatures. Exhaust gas recirculation (EGR) is found to be an effective method to control the level of NOx and smoke emissions caused by the compression ignition (CI) engines. The EGR reduces the amount of NOx and smoke emissions by decreasing the content of concentration of oxygen in the combustion chamber and also in the heat absorption. In order to get clean exhaust, many configurations have been proposed like high- and low-pressure loop EGR, as well as the hybrid systems. In order to reduce the higher level of NOx and smoke particles, the EGR is implemented in homogeneous charge compression engine (HCCI) engine, which gives more promising result by reducing the pumping work and increasing the efficiency of the engine. Here we are studying in detail about the performance and the control of emissions in case of CI, HCCI and the implementation of EGR in the HCCI engine, and how it is useful to reduce the pollution content.