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Active Turbine Tip Clearance Control Trade Space Analysis of an Advanced Geared Turbofan EngineTip clearance within the high pressure turbine of a gas turbine engine is a significant factor in engine performance and efficiency. In the pursuit of higher efficiency, aero-engine designs are migrating toward compact gas turbine (CGT) technology that seeks to increase the bypass ratio of the gas turbine engine without increasing the size of the fan, which is constrained by its underwing location. The reduced size of CGTs invoke concern over increased sensitivity of engine performance due to turbine tip clearance gap that makes an argument for advanced tip clearance mitigation and control techniques to be employed. This paper evaluates the tip clearance trade space for a conceptual geared turbofan engine with a CGT core. This is accomplished through a modeling and simulation approach that includes a sensitivity analysis of engine performance in response to high pressure turbine tip clearance as well as an evaluation of the sensitivity of tip clearance to various design parameters, including material properties and component cooling characteristics. Also included is a parametric study of actuators that provides preliminary requirements for implementation of active turbine tip clearance control actuation systems. The results produced from these studies are meant to be informative, with special emphasis on the demonstration of a systematic approach. The modeling approach appears to capture expected trends. The studies suggest that the tip clearance gap will have a greater impact on the new CGT engines and that a relatively slow, actively controlled actuation system may be sufficient as long as it has control authority to both open and close the tip clearance gap.
Document ID
Document Type
Kratz, Jonathan L.
(NASA Glenn Research Center Cleveland, OH, United States)
Chapman, Jeffryes W.
(NASA Glenn Research Center Cleveland, OH, United States)
Date Acquired
October 24, 2018
Publication Date
July 9, 2018
Subject Category
Aircraft Propulsion And Power
Report/Patent Number
Meeting Information
Meeting: AIAA Propulsion and Energy Forum
Location: Cincinnati, Ohio
Country: United States
Start Date: July 9, 2018
End Date: July 11, 2018
Sponsors: American Inst. of Aeronautics and Astronautics
Funding Number(s)
WBS: WBS 081876.
Distribution Limits
Work of the US Gov. Public Use Permitted.
tip clearance control
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