Device and method for exhaust gas circulation of internal combustion engine

摘要

In an exhaust gas recirculation apparatus for an internal combustion engine mounted with a turbocharger in which a turbine is disposed in an exhaust passage and a compressor is disposed in an intake passage, when the exhaust gas recirculation is carried out, a port formed at the intake passage on the downstream side of the compressor is opened. As a result, since an intake air on the downstream side of the compressor is released to the atmosphere and a negative pressure in the exhaust passage is lowered, a differential pressure between an exhaust pressure in the intake passage and the negative pressure in the intake passage is increased, to improve an exhaust gas recirculation rate, so that a NOx discharge amount can be reduced.