Dean Equations Extended to a Rotating Helical Pipe Flow

In this paper, the fully developed laminar flow in a rotating helical elliptical pipe is examined theoretically. This study focuses on the combined effects of the rotation, the curvature, the torsion, and the shape of cross section. The secondary flow and the fluid particle trajectory are discussed for different elliptical cross sections in the range of -2<=(sigma)<=1, where (sigma) represents the ratio of the Coriolis force to the centrifugal force.