A computational study of saddle point separation and horseshoe vortex system
Abstract
Incompressible flow around a cylinderend wall junction has been simulated by solving the incompressible NavierStokes equations in three dimensions. The equations, cast in generalized curvilinear coordinates, are solved in time as a hyperbolic system by adding a pressure term in the continuity equation and are marched to a steady state. Various physical quantities associated with the saddle point of separation and the horseshoe vortex system are calculated. Computational and experimental results are generally consistent. The skin friction and the pressure distribution on the end wall are consistent with the physics of the problem. Secondary flows both in front of the cylinder and behind it are predicted that are in qualitative agreement with flow visualization results. The calculations also indicate a strongly nonuniform pressure loading along the length of the cylinder. A new mechanism for the existence of the recirculation bubbles behind the cylinderend wall with relatively low ratio of cylinder height to the approaching boundary layer thickness is observed which is markedly different from its twodimensional counterpart.
 Publication:

AIAA, Aerospace Sciences Meeting
 Pub Date:
 January 1985
 Bibcode:
 1985aiaa.meetV....K
 Keywords:

 Cylindrical Bodies;
 Incompressible Flow;
 Saddle Points;
 Separated Flow;
 Vortex Breakdown;
 Wall Flow;
 Computerized Simulation;
 NavierStokes Equation;
 Pressure Distribution;
 Skin Friction;
 Space Shuttle Main Engine;
 Three Dimensional Flow;
 Fluid Mechanics and Heat Transfer