Large Hydropower Water-filled Spiral Case By Force And Plant Dynamic Analysis

With the continuous development of the domestic hydroelectric industry, the unit capacity of the existed power station and the power station under construction is becoming larger and larger. The HD values of the spiral case also grow rapidly. Choosing the right embedding manners is one of the key points to guarantee the safe and steady working performance of the hydraulic turbine generator unit. In order to give full play to the steel spiral case, lower the stress of outside concrete, reduce the ratio of reinforcement and make the structure of the spiral case safe, reliable, economical and convenient, to a giant hydraulic structure with high HD value, the preloading filling spiral case structure is mostly applied at domestic and aboard. The most crucial issue to preloading filling spiral case is the responsible choice of preloading water head and accurately achieve outside concrete state of stress. Due to the complex structure and the larger difference between the every actual project, the study of combined bearing structure is a very complicated subject. In addition,the underground powerhouse of the large-scaled station, as an important part of hydropower station, often induces serious vibration problem, which brings various harm to run of the station, even give rise to danger of the whole station. So, the vibration of the powerhouse has been given a common emphasis.Therefore, this paper is focused on the above questions. Taking the substructure of a hydropower station in Yunnan as an example, Applying ANSYS program, we established whole 3D finite element model for the stress analysis of the preloading filling spiral case structure, gained the stress distributed disciplinarian and displacements. Secondly, we analyze the dynamic characteristics of the powerhouse under different condition. In addition, fifteen kinds of vibration source from the hydraulic, mechanic and electrical factors is give a detailed introduction and analysis. Based on the result of analysis, the resonance is calibrated. Finally, has made Seismic analysis of powerhouse and give the safety evaluation.