Gas turbine engine nacelle

摘要

An initial geometry for a nacelle provides an intake at the upstream end of the nacelle and an exhaust at the downstream end of the nacelle. The intake has, in flow series, an intake lip and a diffuser. The intake lip has a highlight defining the boundary between the inner and outer surfaces of the intake lip. On all longitudinal sections containing the axis of the engine (i) the inner and outer surfaces are tangency matched at the highlight, and (ii) the inner and outer surfaces have their maximum curvatures at the highlight. A method of designing a nacelle for a gas turbine engine includes the steps of:
defining such an initial geometry for the nacelle;
altering the shape and/or position of the highlight; and
obtaining an altered geometry for the nacelle by adjusting surfaces of the intake neighbouring the altered highlight to smoothly blend the altered highlight to unadjusted surfaces of the intake further removed from the altered highlight.