Dynamic blade tip clearance control of aero-engine by the integration of cooling air with fuel thermal management system

Abstract

In advanced aero-engines, the precise control of tip clearance and thermal management of the fuel system are two important measures to improve the transient performance of the aero-engine. In order to optimize the overall performance of an aero-engine during a full-flight mission, this paper proposed a novel architecture integrating active clearance control system and aero-engine fuel thermal management system, which utilizes fuel heat sink to achieve indirect regulation of the tip clearance. Furthermore, a set of critical optimization criteria for the new architecture was derived to achieve dynamic heat distribution in the fuel thermal management system. Subsequently, the transient performance was tested under a complete flight mission with a duration of 10,000 s. The calculation results indicate that the new architecture effectively raises the fuel temperature to its maximum allowable value during low thermal load phases, which increases heat dissipation capability of the system. The new architecture exhibits a significant effect on the control of the tip clearance during the ground idle, cruise, and engagement phases, resulting in a maximum increase of 1.86% in the relative efficiency of the high-pressure turbine. The new architecture also prevents the engine from experiencing excessively narrow tip clearance during acceleration. Ultimately, the new architecture achieves a 2.59% reduction in total fuel consumption compared to the original design. The new architecture has significant potential to improve engine efficiency and increase operational safety.