Gas Turbine Engine with Variable Overall Pressure Ratio

摘要

A gas turbine engine has a variable overall pressure rate ("OPR"). The engine includes a high pressure compressor having at least a primary stage having a set of primary rotors and a secondary stage having a set of secondary rotors. A clutch is provided to selectively engage the secondary rotors with the primary rotors. Engagement of the clutch may be controlled based on the vehicle travel mode, such as disengaging during a takeoff mode to reduce turbine entry temperature and engaging during a loiter mode to increase OPR.