Modeling engines with pulse converted exhaust manifolds using one- dimensional techniques

摘要

One-dimensional "wave-action" codes are widely used by internal combustion engine manufacturers. However, the modeling of multi-pipe junctions within such simulations presents a problem, since the geometry of the junctions cannot be represented fully using a one-dimensional approach, and it can produce a strongly directional effect on the propagated waves. "Pressure-loss" models of junctions have been devised as boundary conditions for one-dimensional simulations, these allow the some geometry induced effects to be introduced into the calculation. This paper examines the performance of such models, when used to simulate a pulse converter-type junction, under unsteady flow conditions.