Study of the Effects of Lacing Rods Location on Natural Frequencies in Last Stage Blades of a Steam Turbine

Subject Areas : Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering

مهدی نوذرپور ¹ , عباس رهی ²

1 - دانشجوی کارشناسی ارشد، دانشکده فنی و مهندسی، گروه مکانیک، دانشگاه آزاد اسلامی واحد اهواز
2 - استادیار دانشکده مهندسی مکانیک و انرژی، پردیس فنی و مهندسی شهید عباسپور، دانشگاه شهید بهشتی

Received: 2015-09-28 Accepted : 2015-09-28 Published : 2012-12-21

Keywords: Finite Element Method, Lacing rod, Turbine blades, resonance,

Abstract :

In this study, effects of lacing rods location on natural frequencies of last stage of a Steam Turbine Blades (STBs) have been investigated. STBs are critical and important elements in a turbine as well as power plants. One of the most important parameters in turbine blades is lacing rods location. In this paper, first, a three dimensional (3D) scan was used to produce the geometrical model of the blade. Then, last stage of a low pressure turbine have been produced and simulated by assembling of the one-blade model. There are two rows of lacing rods in the last stage of turbine. In this paper, effecting the lacing rods location on natural frequencies of system has been studied. According to the Campbell diagrams, the results showed there is no resonance in the last stage blades of the steam turbine for different locations of the lacing rods.

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