Review on the Axial Turbine Long-blade Stage Characteristics under Off-design Conditions

doi:10.3901/JME.2024.08.271

Abstract

Abstract: To meet the needs of higher load, efficiency and reliability axial turbine, the blades are designed longer. Compared with shorter blades, the profiles of long blades are torsional and flow parameters are different along the blade height, and its design is more difficult relatively. The long blade stage always operates under off-design conditions, so the stage has complex flow structure and its performance deteriorates, which easily leads to the decline of blade safety and service life. In order to facilitate scholars to further study the characteristics of long blade stage under off-design conditions，and further explore the methods of broadening the operational condition range of long blade stage, a series of relevant literatures are surveyed. Firstly, the aerodynamic and structure design characteristic of long blade are introduced. Secondly, the aerodynamics characteristic, heat transfer as well as strain characteristics of long-blade stage under off-design conditions are analyzed and summarized，besides the influence of exhaust hood on last long blade stage under variable conditions is introduced. Finally, the existing deficiencies are introduced based on the latest research progress, and the future research focus and development trend of axial turbine long-blade are discussed.

Key words: axial turbine, long-blade stage, off-design

CLC Number:

TG156

HUANG Gongrui, ZHU Yangli, XIONG Jun, WANG Xing, LI Wen, CHEN Haisheng. Review on the Axial Turbine Long-blade Stage Characteristics under Off-design Conditions[J]. Journal of Mechanical Engineering, 2024, 60(8): 271-290.

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