During the operation period, the deformation of an ultra-high arch dam is affected by the large fluctuation of the reservoir water level. Under the dual coupling of the ultra-high dam and the complex water level conditions, the traditional variational analysis method cannot be sufficiently applied to its deformation analysis. The deformation analysis of the ultra-high arch dam, however, is very important in order to judge the dam safety state. To analyze the deformation law of different parts of an ultra-high arch dam, the panel data clustering theory is used to construct a Spatio-temporal characteristic model of dam deformation. In order to solve the difficult problem of the fluctuating displacement of dam deformation with water level effect, three displacement component indexes (absolute quantity, growing, and fluctuation) are proposed to characterize dam deformation. To further optimize the panel clustering deformation model, the objective weight coefficient of clustering comprehensive distance is calculated based on the CRITIC (CRiteria Importance Through Inter-criteria Correlation) method. The zoning rules of the ultra-high arch dam are established by using the idea of the CSP (Constraint Satisfaction Problem) index, and the complex water level of the reservoir is simulated in the whole process. Finally, the dynamic cluster analysis of dam deformation is realized. Through a case study, three typical working conditions including the rapid rise and fall of water level and the normal operation are calculated, and the deformation laws of different deformation zones are analyzed. The results show that the model can reasonably describe the deformation law of an ultra-high arch dam under different water levels, conveniently and intuitively select representative measuring points and key monitoring parts, effectively reducing the analysis workload of lots of measuring points, and improve the reliability of arch dam deformation analysis.

The hydrodynamic performance of a turbine with multi-degree of freedom (rotation, rolling, surging) coupled motion in the unbounded uniform flow is analysed by the sliding and dynamic meshes. The effects of the turbine's hydrodynamic load has been studied and illustrated considering the coupled motion of rotation, rolling and surging. Numerical results shows that: 1) the effects of the hydrodynamic load is mainly caused by the surging motion, namely, the instantaneous values of the axial load and power coefficients generate fluctuation with a frequency that is the same as that of the surging and an amplitude that similarly increases in parallel. The effect of the rolling motion on hydrodynamic load will be reflected when its frequency is greater than that of the surging; 2) the calculation formulas of the turbine's axial load and power coefficients has been obtained. The results of the hydrodynamic load calculated by the calculation formula and CFD numerical simulation show good agreements, which verify the calculation formulas. The results of this research can provide relevant data for the hydrodynamic analysis of turbines with multi-degree of freedom motion and verify the structural design and control of the electric output.

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