The flow field around five transonic inlet lips at high incidence is investigated for a variety of
flow conditions around a design point representative of high incidence manoeuvring. Changes
to the operating point are simulated by varying the angle of incidence as well as changing the
mass flow rate over the lip, intended to mimic the effect of an increase in engine flow. For these
inflow conditions, the flow on the surface of the lip is characterised by a supersonic region,
terminated by a near-normal shock wave. Of particular interest is the effect of lip geometry
and operating point on the boundary layer at the equivalent fan location.
The parametric investigation revealed a significant effect of lip shape on the position and
severity of the shock wave-boundary layer interaction. From correlation studies based on the
parametric investigation, it appears that the extent of shock-induced separation is the main
factor affecting the boundary layer state downstream of the normal shock wave-boundary layer
interaction. Somewhat surprisingly, this was found to be independent of shock strength but
potentially related to the severity of the diffusion downstream of the shock. Alongside delaying
flowreattachment, this diffusion is also likely to have a direct detrimental effect on the boundary
layer development close to the engine fan