A Comparison Between Different EGR Systems for HD Diesel Engines and Their Effect on Performance, Fuel Consumption and Emissions

Abstract

<div class="htmlview paragraph">An effective way of meeting future emission legislation with a heavy-duty diesel engine is to equip the engine with an EGR-system combined with a particulate trap. In this study the work was concentrated on the EGR-system. The goal of the investigation was to find an EGR-system that could deliver enough air and exhaust gases to the engine to meet the Euro IV emission levels with minimum penalty on engine performance and fuel consumption, starting from a Euro 0 engine. The tests showed that it was possible to significantly improve emissions with all the tested EGR-systems in combination with a particulate trap, but notable differences with respect to fuel consumption were found.</div> <div class="htmlview paragraph">For all EGR systems under study, the main factors influencing engine performance and fuel consumption were found to be.</div> <div class="htmlview paragraph"> <ul class="list disc"> <li class="list-item"><div class="htmlview paragraph">Pumping losses.</div></li> <li class="list-item"><div class="htmlview paragraph">Residual gases.</div></li> <li class="list-item"><div class="htmlview paragraph">Temperature of the recirculated exhaust gases.</div></li> <li class="list-item"><div class="htmlview paragraph">Distribution of the recirculated exhaust gases between the cylinders</div></li> </ul> </div>