A non-linear quasi-3D model with Flux-Corrected-Transport for engine gas-exchange modelling

Abstract

Modelling has proven to be an important tool in the design of manifolds and silencers for internal combustion engines. Although simple 1D models are generally sufficiently precise in the case of manifold models, they would usually fail to predict the high frequency behaviour of modern compact manifold designs and, of course, of a complex-shaped silencing system. Complete 3D models are able to account for transversal modes and other non-1D phenomena, but at a high computational cost. A suitable alternative is provided by time-domain non-linear quasi-3D models, whose computational cost is relatively low but still providing an accurate description of the high frequency behaviour of certain elements. In this paper, a quasi-3D model which makes use of a non-linear second order time and space discretization based on finite volumes is presented. As an alternative for avoiding overshoots at discontinuities, a Flux-Corrected Transport technique has been adapted to the quasi-3D method in order to achieve convergence and avoid numerical dispersion. It is shown that the combination of dissipation via damping together with the phoenical form of the anti-diffusion term provides satisfactory results