Modeling and analysis of oscillations of the steam turbine with a capacity of 500 MW

• Main Author: S.V. Krasnikov
• Format: Article
• Language: English
• Published: Kharkiv National Automobile and Highway University 2019-05-01
• Series: Avtomobilʹnyj Transport (Harʹkov)
• Subjects: vibration; steam turbine; low pressure case; finite element method; oscillations; foundation
• Online Access: https://dspace.khadi.kharkov.ua/dspace/bitstream/123456789/2667/1/AT_44_10.pdf

Problem. The main problem of the vibrational reliability of steam turbines is considered, which is connected with the appearance of increased vibration in the bearings of the turbine rotor. The root cause of the increased vibration of these parts of the turbine is the rotor's non-balance. However, the case of operating practice is considered, where rota-tional alignment did not significantly change the vi-bration parameters. Goal. The purpose of this work was to simulate the forced oscillations of the turbine-foundation-base system with turbine K-500-65 / 3000 KTGZ, as well as to investigate the causes of in-creased vibration of the rotor supports. Methodology. The research was carried out using the method of quantum, the method of finite elements, and also by the author's developed methods for constructing models and carrying out research on oscillations of the turbine-foundation-base system. Results. As a result of the conducted studies, a three-dimensional finite element model of the turbine-foundation-base system was obtained, and amplitude-frequency de-pendences for the rotor supports were also obtained. The conducted research made it possible to draw conclusions about the causes of increased vibration of the rotors of the steam turbine. Originality. The type of the developed three-dimensional models of the turbine-foundation-base system is unique. Due to the features of this model, it is possible to study the vibrational processes at the level, which allows you to analyze the vibrations of almost all elements of the system. For individual studies, further specification of the parts of the system important for the task is needed. This allows us to use the features of the finite element method to specify the turbine-foundation-base system in accordance with the actual operating conditions. Other methods and approaches did not resolve the established problem and explained the reasons for the hanging vibration of the turbine rotor supports. Practical value. The practical significance of this work is visual means of developing specialized models for studying forced oscillations of the turbine-foundation-base system, as well as solving a practical problem in analyzing the causes of increased vibration of the rotors of the steam turbine. The results of the work were used to develop measures to improve the vibration state of power units with steam turbines of 500 MW capacity.