Flow Prediction in an Axisymmetric Inlet Valve/Port Assembly Using Variants of k—ε

The paper describes a computational investigation of steady incompressible air flow through an enlarged-scale version of an axisymmetric intake valve/port assembly. The numerical procedure used for this purpose solves the governing equations using the SIMPLE algorithm. The governing equations are expressed in a general curvilinear coordinate system and are discretized in a finite volume fashion. The time-averaged governing equations are closed using four different variants of the k—ε turbulence model. In addition to the standard model, which is known to be deficient in predicting strongly curved flows with steep pressure gradients, a variant was tried in which the dissipation equation is sensitized to irrotational strains. The third alternative involved a two-layer representation employing a one-equation model in the near-wall viscosity-affected region and the standard k—ε model in the core region. The fourth model employed was developed from the combination of the last two. The predictions are assessed by comparing the available experimental flow field data. The fourth model showed substantially improved qualitative behaviour and good quantitative agreement in comparison to the other alternatives.