Abstract: The boundary perturbation solutions for blood flow between two relatively rotating concentric cones (one is stationary and the other is rotating with constant angle velocity ω) have been obtained[1]. On the basis of the solutions obtained and by using theory of the narrow gap stability, the stability of the stratified blood flow between two relatively rotating concentric cones with an axial flow is demonstrated.

Key words: two dimensions RLW equation, cnoidal wave solution, periodic solution, uniqueness