Numerical simulation of separating boundary-layer flow

A two-dimensional boundary-layer flow over a bump has been studied computationally by solving the incompressible Navier–Stokes equations. The numerical solution procedure uses a mapping transforming the physical coordinate system into a Cartesian one. The resulting system is solved using a mixed finite differences––Chebyshev collocation discretization. We compare the influence matrix technique with a fractional time-step procedure used to enforce the divergence-free condition. Numerical experiments are performed for bumps with different aspect ratios. The separation structure is investigated for increasing Reynolds number and self-induced vortex shedding is reproduced numerically.