A boundary layer energiser

摘要

A boundary layer energiser (20) for energising a boundary layer flow (33) over a surface (22), the boundary layer energiser (20) comprising one or more passages (24) terminating in one or more respective holes (26) provided on the surface (22), wherein the one or more passages (24) comprises at least one fin (25) configured so as to generate a vortex flow in the one or more passages (24) such that, when in use, a fluid emanating from the one or more passages (24) flows in a vortex.