Abstract
In order to improve the accuracy of the numerical prediction of gas flow in intake ports, a porosity approach has been applied to control volumes adjacent to walls. Numerical prediction of intake port flow has been carried out under steady flow conditions. By comparing the results of numerical predictions using the porosity approach with those using the previous approach of representing wall surface with staircaselike boundaries, it was confirmed that the accuracy of flow prediction was improved considerably by using the porosity approach. It has therefore become feasible to predict pressure losses in intake ports quantitatively. Consequently, an improvement in accuracy is expected in the prediction of volumetric efficiency and swirl intensity under the operating conditions of actual engines by applying the porosity approach.
