Nonuniqueness of separated flow past nearly flat corners
Nonuniqueness of flow pattern associated with flow separation is shown to exist in case of an incompressible flow in the neighbourhood of a nearly flat convex corner at high Reynolds numbers. The boundary layer in this region has a triple-deck structure, the bottom deck, a viscous boundary layer, being the most important one. This layer is described using an orthogonal coordinate system moving with the surface of the body, whose origin is located at the corner point, and using dimensionless variables. It is shown that the already known solution is only one branch of possible solutions of the equations set up, and that a second branch exists and is physically characterized by a longer separation bubble. The problem under consideration is solved numerically by a second-order- accurate finite-difference scheme, by using the Newton's method for solving the nonlinear system of equations obtained and using the matrix sweep method for inverting the Jacobi matrix in each iteration. For further information the reader is referred to the quoted literature. The results in dependence on the corner angle are discussed in detail.
second-order- accurate finite-difference scheme
scientific article; zbMATH DE number 536749