Electronic flow control for a stratified EGR system

摘要

A stratified exhaust gas re-circulation (EGR) engine uses an exhaust port per cylinder for exhausting exhaust gases and to re-circulate exhaust gas. The EGR valve may be phased from the exhaust stroke to the intake stroke. The EGR valves that control the exhaust gas re-circulation ports may be on a separate camshaft from the other valves. The EGR ports and an intake port for each of the cylinders may be helical or tangential ports that stratified the exhaust gas and the air in the cylinder. The engine may be a direct injection or a port fuel injection engine with one or more exhaust manifolds. The exhaust gas re-circulation ports may be controlled by a single flow valve or each port may have a separate flow valve. The intake ports may be controlled by a single flow valve or each intake port may have a separate flow valve.