Dynamic Analysis Of Top Overflow Powerhouse

As the characteristic and functional needs of structure, the vibration of powerhousecommonly during operation.BingLing overflow powerhouse are not only generating buildingsbut also water retaining and discharge structure, meanwhile, the upstream and downstreamface of the power house direct contact with water, there is mutations of stiffness and mass ofpowerhouse along with the height of power house, so it is important to analyze the structurestability and the structural vibration responses which induced by fluctuating pressures of flowand dynamic loads. At present, researches on vibrations of top overflow hydropower housesare few. In this paper based on the first top overflow powerhouse under construction inChina, the dynamic responses of the overflow powerhouse under the combined actions ofdifferent dynamic press are calculated, including the dynamic responses of power houseunder the fluctuating pressure of flow and dynamic loads from the bulb hydro generators.Thereafter resonance check was made by analyzing some possible excitation sources. Theresults researched will provide a theoretical basis for optimizing the dynamic characteristicsof the overflow powerhouse structure of bulb hydro generator power plant and improving itsresonance design. Its primary context involves following aspects:(1) Analyze some possible excitation sources of BingLing top overflow powerhouseunder operating, including the frequency of hydraulic fluctuation, disequilibriumelectromagnetic force and mechanical force, and analyze the amplitude and frequencycharacteristics of possible excitation sources.(2) A more realistic three-dimension model of single unit—block is made; Thedynamic characteristic of the overflow powerhouse are calculated. In order to reflect thedynamic characteristic of whole and partial of top overflow powerhouse, the differentmodels are made.(3) By analyzing the pulsating pressure data taken from the model test on hydraulicpowerhouse by design institute, the conversion coefficient of fluctuating pressurefrom-point-to-area was deduced through the correlation analysis theory.(4) Analyze the dynamic response of whole structure under the pulsating pressurewhich multiplied by conversion coefficient and dynamic loads from the bulb hydro generators.The accuracy of calculation is high enough for practical purposes. The standards of powerhouse vibration are discussed, a safety evaluation on the vibration of powerhouse hasbeen made, and some suggestions on vibration reduction measure have been provided.(5) Analyze the dynamic loads generated by the bulb hydro generators whether itinduced the powerhouse resonance or not.(6) Analyze the dynamic response of whole structure under the overflow pulsatingpressureBased on a summary of the research in the papers, some proposals to further study onthis problem have been made.