Journal of Fluid Mechanics

Further contributions on the two-dimensional flow in a sudden expansion

a1 Lehrstuhl für Strömungsmechanik, Cauerstr. 4, 91058 Erlangen, Germany
a2 Department of Chemical Engineering, University of Alberta, Edmonton, Alberta, Canada, T6G 2G6


Two-dimensional laminar flow of an incompressible viscous fluid through a channel with a sudden expansion is investigated. A continuation method is applied to study the bifurcation structure of the discretized governing equations. The stability of the different solution branches is determined by an Arnoldi-based iterative method for calculating the most unstable eigenmodes of the linearized equations for the perturbation quantities. The bifurcation picture is extended by computing additional solution branches and bifurcation points. The behaviour of the critical eigenvalues in the neighbourhood of these bifurcation points is studied. Limiting cases for the geometrical and flow parameters are considered and numerical results are compared with analytical solutions for these cases.

(Received December 18 1995)
(Revised July 19 1996)