Effects of HPL and LPL-EGR System on Wide Range and High Rate EGR in High Boost Multi-cylinder Diesel Engines

Abstract

The authors have shown that it is effective to reduce BSNOx and PM by high rate EGR. But it is not easy that the wide range and high rate EGR is achieved in high boosted and inter-cooled diesel engine, because increasing of EGR flow in high pressure loop decreases total flow passing turbocharger. The combination system of both high and low pressure loop EGR is able to increase EGR rate and boost pressure in comparison with a case of only high pressure loop EGR system, and it reduces exhaust emissions and fuel consumption effectively.