The effect of high/low pressure EGR system on performances of a diesel engine
XIN Zhipeng
YANG Lijun
GUO Zhao
TIAN Jiangwei
Abstract：In order to improve the performance of a diesel engine,optimize emissions and reduce fuel consumption,advantages and disadvantages of high/low pressure(HP/LP)exhaust gas recirculation(EGR)are analyzed.A 2.0 L diesel engine equipped with HP/LP-EGR system is tested on the bench and vehicle to study the impact of HP/LP-EGR system on diesel engine performance.The results show that fuel consumption and emissions can be effectively reduced by matching HP/LP EGR system and applying it rationally,compared with diesel engines with HP EGR system,the combined application of HP/LP-EGR system can reduce fuel consumption by 3.1%,NOx emission by 3.0%,and PM emission by 22.2%.The application of LP EGR system can reduce the amount of exhaust gas flowing through the intake manifold,thereby improving the intake manifold coking problem.The EGR system may freeze when the intake system is used in a low temperature environment.The HP/LP EGR system should be closed based on the ambient temperature to avoid engine damage caused by ice.
Keywords：HP EGRLP EGRfuel consumptionemissioncokingice formation
Publication Date：2024-06-28
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：6( 62-67 )