Critical Evaluation of Methods for Imposing Solid-Wall Boundary Conditions inInviscid Flow

摘要

This report presents a critical evaluation of widely used methods for imposingdiscrete solid-wall boundary conditions for the numerical computation of inviscid flows. Specifically, it shows that some of these methods are only provisionally correct. Also, an explanation is given for the success of others. In particular, the report shows that a method involving contravariant velocity components can generate distortions in computed flows. Because complex CFD calculations can be difficult to interpret, the claims made here are demonstrated with explicit solutions to simple model problems. This work emphasizes that subtle and erroneous effects can result from the use of apparently natural numerical methods. It also emphasizes the importance of developing simple tests for these computational methods to elucidate the possible consequences of their use. Solid-wall boundary, Velocity, Computational methods, Inviscid flows.