DYNAMIC ANALYSIS OF A ROTARY HOLLOW SHAFT WITH HOT-FIT PART USING CONTACT ELEMENTS WITH FRICTION

Abstract

One of the key factors in designing a motor built-in high speed spindle is to assemble the motor rotor and shaft by means of hot-fit. Presented in this paper is a study of the influence of a hot-fit rotor on the local stiffness of the hollow shaft. Dynamic analyses of the rotor-hollow shaft assembly using contact elements are conducted. The normal contact stress state between the rotor and the hollow shaft is obtained through the use of contact elements with friction effects included. The normal contact stress, considered as the pr-stress between the rotor and the hollow shaft, is then adopted for subsequent modal analyses. In this study, the modal analysis results are verified by a modal testing experiment. The percent errors of the first natural frequency and the second natural frequency are down to about 0.58% and 0.79%, respectively.