Exhaust gas purification apparatus for an internal combustion engine

摘要

A catalyst is disposed close to an internal combustion engine, while making uniform a concentration of an additive agent in an exhaust gas flowing into the catalyst. Provision is made for a supply device (4) to supply the additive agent into the exhaust passage (2), a catalyst (3) arranged at a downstream side of the supply device (4), a bent portion (23) being a location at which the exhaust passage (2) bends, and being formed at the downstream side of the supply device (4) and at the upstream side of the catalyst (3), and a swirling flow generation part (1) formed in the bent portion (23) so as to permit an exhaust gas to come therein on an extension line in a direction of movement of the exhaust gas which flows toward the bent portion (23) at the upstream side thereof, thereby to generate a swirling flow at the downstream side of the bent portion (23).