Structural Research On Spiral Case Of Water Turbine In Large Hydropower Station

With the rapid development of the hydroelectric industry in our country, now enlarging the unit capacity is the chief tendency. The higher unit capacity, the lower cost, but a series of puzzles in the design, manufacture, erection and operation etc of the spiral case have appeared. More attentions should be paid to the natural frequency of vibration and the temperature stress of the concrete of the spiral case.In accordance with the practice of a large hydropower station, a systematic study has been carried out in this paper. The paper is divided into seven chapters. First, a brief introduction about some main patterns of the spiral case and the general design methods are presented. Then, basing on the finite element theory, a calculation model is set up by using Super SAP and ANSYS. Moreover, A finite element calculation has been performed in the static and dynamic analysis, as well as the temperature stress and nonlinear property, with the leading of the corresponding principles. At last, some suggestions on the further research are proposed.During the modeling and calculating, the simulation of the steel shell, the cushion layer, the concrete and the rebar etc is as accurate as possible in order to reflect the characteristic of the structure. As a result, some useful conclusions are drawn and can be referred to other similar projects.