Flow Separation Control of a Vertical Stabiliser Using a Rudder-Mounted Slat

A joint study utilising experimental and numerical methods was carried out to investigate the aerodynamic effect of a rudder-mounted slat on a vertical stabiliser. The wind tunnel test results showed that the side force coefficient was increased more than 3% with a negligible increase in drag when the rudder deflection angle was set to δ = 30°. Large eddy simulation (LES) results suggested that the rudder-mounted slat can increase the circulation around the vertical stabiliser, showing that the flow from the upstream recirculating regions was drawn towards the rudder surface. Associated changes in the turbulent flow field, including the mean and turbulent flow field and the vortical structure are also presented to understand the flow control mechanism by the rudder-mounted slat.