Investigation of the upstream end effect on the flow characteristics of yawed circular cylinders

Abstract

The flow over a yawed circular cylinders is a research area of current interest in aerodynamics due to the inherent similarities with that of the swept wing configuration. These models however, must be carefully mounted in order to suppress a phenomenon known as attachment line contamination. This contamination occurs when models span the entire test section width, exposing the flow to the highly disruptive test section wall turbulent boundary layers. One way of suppressing this phenomenon is to mount the upstream end of the model off the test section wall, whereby eliminating the interaction between the boundary layer and the model. Mounting the model with the upstream end free of the wall however, introduces end effects which are transported inboard from the downwash over the free end.