Impact of intake pipe's structure on the non-uniformity of intake air for diesel engine with one - and three -dimensional coupled simulation model

AVL BOOST and AVL FIRE were employed to establish a one dimensional thermal dynamic simulation model and a three dimensional fluid simulation model of intake pipe for a V-type 8-cylinder diesel engine respectively. The coupled simulation of one-dimensional model and three-dimensional model was adopted to analyze the non-uniformity of intake air between a II-type intake pipe and a ring intake pipe as well as the transient flow field inside the manifolds with different crank angle. It is showed that there is an air snatch effect between the two cylinders in fire order on the same side; compared with the II-type intake pipe, the ring intake pipe can amplify the volume of inlet air room and reduce the air snatch effect which may ease induction distribution unevenness for the diesel engine.