Study On Surge Chamber Resistance Coefficient In Hydropower Engineering

With the development of hydropower construction and after a long-term study ofhydraulic structure design and practice by hydropower researchers, there have been verymature means to solve hydraulics problems. As a major part of the water system ofhydropower engineering in those hydropower constructions, Surge chamber is still the focusof scholars and design research units concerned. The determination of the size and type ofsurge chamber depends on the environment and conditions of hydropower projects, and thenon the calculation of the hydraulic transition process in the design stage. The accuracy of thepressure loss coefficient the surge chamber has a significant impact on the calculation ofhydraulic transition process, so the loss of surge chamber drag coefficient selected inhydropower construction in the surge chamber has a major impact on the security of thehydropower and also the success of the whole project. In the past, the research on the surgechamber is primarily through to established the hydropower station surge similaritytransformation physical model, then carry out experimental test. With the improvement ofcomputer hardware and software technology, more and more scholars use computational fluiddynamics (CFD) to research on the internal flow of the surge chamber.The factors influencing the impedance type of surge impedance loss coefficient are: theshape, size of the model and its connection with surge chamber method and so on. this paperstudy surge simulation model with FLUENT, analyze the relationship between pipe lengthand partial loss, then Simulate the numerical simulation loss coefficient resistance accordingto the real size of an oversea hydropower, apply the results to transient computing andanalyzing of hydropower station.The main work and results are as follows:1. Simulate two typical surge chamber model with FLUENT, then make a comparativeanalysis with the experimental results of literatures put forward analysis, the results show thatthere is a good agreement between two numerical curves, so FLUENT numerical simulationcould be used to study the surge chamber.2. Compare the influence of three times the diameter of the detection surface and fivetimes the diameter of the results on the numerical simulation results. The results show thatthere is a small difference between them, and3times the diameter be selected is fine.3. Simulate four different pipe length impedance surge chamber model and research therelations between connecting pipe length and loss coefficient of local resistance. Comparesimulation data, the results show that with the increase of connecting tube length, theimpedance surge chamber loss of local resistance coefficient is also increasing, and thecorresponding increase is loss of resistance along the connecting tube.4. Simulate the numerical simulation loss coefficient resistance according to the real sizeof an oversea hydropower, and calculate the specific numerical of impedance surge chamber pressure loss coefficient in each flow regimes, then apply the results to transient computingand analyzing of hydropower station.