Evaluation of the outflow boundary conditions for Bi-Global stability analysis of axisymmetric boundary layer

Abstract

The numerical solution of the Bi-Global stability problem in the axisymmetric boundary layers required boundary conditions in the axial and radial directions. It is very dif- ficult to impose physically meaningful boundary conditions in the streamwise direction at inflow and outflow. The twodimensional eigenvalue problem is considered for the BiGlobal stability analysis of the axisymmetric boundary layer. The extrapolated boundary conditions are imposed as an outflow condition with the Homogeneous Dirichlet conditions at the inflow boundary. The temporal and spatial properties are computed with the linear, quadratic and cubic order of extrapolation at the outflow boundary condition. The Linear extrapolation yields the largest temporal and spatial growth than that of quadratic and cubic extrapolation.