A Study of Performances, EGR Distribution and Emission Variation due to Shape Modification of the Intake Manifold in a Diesel Engine

The principle of exhaust gas recirculation (EGR) is that the exhaust gas can be used as an oxygen-depleted gas to be mixed with the fresh, oxygen-rich air and recirculated into the combustion chamber. EGR is a very efficient technology for reducing NOx without any strong adverse effects on other exhaust emissions, thus it is widely used. EGR rate of each cylinder should be as uniform as possible to satisfy the stringent emission regulation. If there are differences in EGR rate between cylinders, there would be emission deviation even with the same fuel injection. In this study, we predicted the effect of the intake manifold shape modifications on the engine performance and EGR distribution rate by using computational fluid dynamics and compared with engine experimental results.