Side Force on Bodies of Revolution: Role of Attached Flow

Abstract

The flowfield past a body of revolution at large incidence may develop an asymmetric wake that induces a significant side force. It remains a challenging problem for both computational and experimental analyses, with massive separation and coexistence of steady and unsteady regions. A number of researchers have studied the complex separated flow on the lee side. This paper focuses on the role played by the attached flow on the windward side. Solutions obtained with unsteady Reynolds-averaged Navier–Stokes computation, shown to be in good agreement with experimental data, are used to investigate the contributions of the attached and separated regions of the flow to the forces acting on the body. A strongly unbalanced pressure distribution of the attached flow is responsible of most of the side force. A description of the crossflow structure is given to explain the large magnitude of the sectional side force, sometimes exceeding that of the normal force.