| The model known as “triple-deck”, proposed in 1969, independently and almost simultaneously, by Neiland, Stewartson-Williams and Messiter, allows the study of a laminar boundary-layer as it is subjected to a local “disturbance” on the solid surface. The objective of this model is to determine the inception conditions for first boundary layer separation. F. T. Smith and other researchers used the technique mentioned above to study the flow over a small hump on a flat plate for various hump dimensions and flow conditions. It was observed that the disturbance is manifested by a rapid evolution of the flow in both the tangential and normal directions to the solid surface.; In this work, the triple-deck model is applied to a small disturbance located on a curved object. The detailed order of magnitude analysis resulted in a triple-deck structure similar to that obtained for the flat plate. However, the free stream pressure distribution is no longer constant as in the case of flow over a flat plate. Consequently, the flow structure and the conditions necessary to cause separation are altered. The case of flow over a sphere is analyzed for the same hump sizes and profiles described in the work of F. T. Smith. The present results are compared to the flat plate case to elucidate curvature effects. |
