МОДЕЛИРОВАНИЕ И АНАЛИЗ КОЛЕБАНИЙ КОРПУСА ТУРБИНЫ 500 МВт ПРИ СНИЖЕНИИ РАБОЧЕЙ ЧАСТОТЫ

Abstract

Problem. The problem of increased vibration of bodies of a steam turbine cases with a capacity of steam turbine of 500 М W is considered. The m а in cause of the increased vibration of the steam turbine is the rotor's unbalance and insufficient stiffness of the system elements. The c а se of operating pr а ctice is considered, where the rotational alignment did not significantly change the vibration parameters. Go а l . In this work the purpose was to make simulation of the forced kind of oscillations of the low-pressure cylinders flexible bodies in the turbineunit-foundation-base system with a turbine unit K-500-65/3000 KHTZ, to study the different causes of their increased level of vibration in case of less work frequencies. Methodology . Т he research is made using the method of oscillation, the method of finite elements, as well as the author's methods of constructing models and conducting research on oscillations of the turbineunit-foundation-base system. Res и lts . Т h е results of the research is as follows: a three-dimensional complex finite-element model of the turbine-foundation-base system was obtained, as well as the amplitude-frequency dependences for the points of the cylinder body of low pressure. The conducted study made it possible to draw conclusions about the different causes of increased vibration of the parts of the steam turbine unit flexible bodies. Originality . The type of designed three-dimensional models of the turbine unit-foundation-base system is unique. Due to the features of the developed model, it is possible to make a vibration processes study at a low level that enables to analyze the oscillations of complex system elements. For individual kinds of studies, further unique specification of the individual parts of the considered system is required. This enables to use the features of the finite element method to specify the turbine unit-foundation-base system in accordance with the actual operating conditions. Other researchers did not solve the problem or clarified it. Value to practice. The significance of the work done in practical terms is primarily an illustration of the technique as a tool for developing specific models in the study of oscillations of a turbine-foundation-base system, as well as for solving practical problems of concretizing and localizing the causes of increased vibration of individual elements of a complex system. The results obtained in the work were used to improve the vibration state of the buildings of units with a steam turbine power unit with the capacity of of 500 MW.