Optimization of Bearing Location for Multi-Stepped Rotor by Genetic Algorithm

Authors

Department of Solid Mechanics, Faculty of Mechanical Engineering, University of Kashan

Abstract

The optimal design problem of systems contains rotating shafts, so that the system has appropriate vibration characteristics, is one of the most important factors in performance and efficiency of the rotor systems operation. Vibration of rotary equipment are usually caused by factors such as unbalance ,Misalignment, Abrasion Parts and Abrasion moving parts and any other reasons. The frequency of this vibration forces are usually integer multiples of rotating speed (spin rate) so if the initial critical speed is as far away as possible from the rotational speed of the rotor,the rotor works in a safer operational area and other parts of system need to a few period of repairs or revision. In this paper Myklestadt-Prohl method has been used to compute initial critical whirling speed of a multi-stepped rotor and genetic algorithm to optimize the location of the bearings in the rotor, so the first critical speed of the system has maximum value for the least number of bearing.

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Main Subjects


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