For a solid body placed in a high Reynolds number fluid flow, a thin boundary layer appears on the body. In this layer there is a rapid change in the magnitude of the tangential flow from zero at the wall to the free flow value. Typically the flow in the boundary layer is laminar close to the leading edge, but becomes turbulent further downstream. Understanding where the transition point occurs is important when calculating drag. The location of the transition point is sensitive to the presence of unsteady disturbances in the free-stream.

This project is concerned with how disturbances interact with the boundary layer close to the leading edge and then develop downstream [1]. Close to the leading-edge the disturbances are governed by the Linearised Unsteady Boundary Layer Equation (LUBLE). This project will investigate the relationship between two sets of eigenfunctions which arise in the solution - termed Lam-Rott and Brown-Stewartson modes [2]. The importance of Lam-Rott modes in transition analysis is well understood, while Brown-Stewartson modes are much less studied.

The project will combine numerical and analytic techniques and does not necessarily require a background in fluid mechanics or aerodynamics.

This project is also open to applicants (home, EU or Overseas) who have their own funding. 

Hammerton, P.W. & Kerschen, E.J. (1996). Boundary-layer  receptivity for a parabolic  leading edge. Journal of Fluid Mechanics, 310, 243--267 

Hammerton, P.W. (1999) The appearance of Lam-Rott and Brown-Stewartson eigenfunctions in solutions of the boundary-layer equation. Quarterly Journal of Mechanics & Applied Mathematics. 52, 373--385.