A combined experimental/computational study has been performed for flow in rotating serpentine passages which approximate internal cooling passage for turbine blades. Experimental results are presented in the companion, Part I. The numerical simulations were performed using detailed experimental velocity profile measurements, documented in Part I, to set inflow conditions. Incompressible flow predictions with a two-layer k-ε turbulence model, which isolated the Coriolis induced secondary flow, agreed well with the measured velocities. Fluid density variations were included in compressible flow simulations which show the impact of the centrifugal buoyancy force in addition to the Coriolis force. Comparison with previously acquired heat transfer data indicates that the buoyancy force may be important in gas turbine applications.