Boundary Layer Along Annular Walls in a Swirling Flow

The development of incompressible turbulent boundary layers along concave and convex stationary annular walls is investigated analytically and experimentally for a swirling flow; i.e., flow with both tangential and axial mean velocities. It was found that the integral momentum equation describing this type of boundary layer contains three correction terms to the conventional equation. The combined influence of these corrections appears to promote the growth of the boundary layer next to a concave wall. Other differences between the boundary layers with swirl and those without swirl are pointed out and interpreted. Measurements on turbulence intensities appear to confirm such interpretations.