公开(公告)号：US11313241B2

公开(公告)日：2022-04-26

申请号：US17084821

申请日：2020-10-30

Applicant: ROLLS-ROYCE plc

Inventor： Fernando L. Tejero Embuena ,  David G. Macmanus ,  Christopher T J Sheaf

IPC: F01D25/24 ,  F01D9/04 ,  F02C7/04

Abstract: A nacelle for a gas turbine engine having a longitudinal centre line includes an intake lip disposed at an upstream end of the nacelle. The intake lip includes a crown and a keel. The crown includes a crown leading edge and the keel includes a keel leading edge. The crown leading edge and the keel leading edge define a scarf line therebetween. The scarf line forms a scarf angle (θscarf) relative to a reference line perpendicular to the longitudinal centre line. A fan casing is disposed downstream of the intake lip and includes a casing leading edge. The casing leading edge defines a droop line normal to the casing leading edge. The droop line forms a droop angle (θdroop) relative to the longitudinal centre line. A relationship between the droop angle (θdroop) and the scarf angle (θscarf) is given by: θdroop=θscarf/1.5±1 degree.