FURTHER CONTRIBUTIONS ON THE 2-DIMENSIONAL FLOW IN A SUDDEN EXPANSION

Two-dimensional laminar flow of an incompressible viscous fluid throug h a channel with a sudden expansion is investigated. A continuation me thod 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 perturba tion quantities. The bifurcation picture is extended by computing addi tional 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 solutio ns for these cases.