High EGR Diesel Combustion and Emission Reduction Study by Multi Cylinder Engine (Fourth Report) - Effect of variable swirl of multi-cylinder Engine

摘要

Recently the heavy duty diesel engines have adopted the direct fuel injection combined with high injection pressure, the high boost turbo charger and the EGR, which is well known as a means to reduce the NO{sub}x emission. The experiments including the installation of above mentioned technologies have been done under the conditions of intake air quantity up to 4 times of naturally aspirated (NA) engine, 250MPa injection pressure and 70% EGR rate. In these conditions the exhaust emissions such as NO{sub}x and smoke are effectively decreased. The SCD (Super Clean Diesel) multi-cylinder engine was designed by the result of author's previous experiment. And we tested the SCD under high EGR rate and high boosting. We obtained that the variable swirl is very effective way for reducing emissions.