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Recently, with the development of numerical technology of hydrokinetics and computer, there is considerable progress in the research of the three-dimensional turbulence field within the hydraulic machine. The research in reaction water turbine of our country has accumulated abundant experience, even exceed international most advanced level in some field, but lag behind foreign countries advanced producer far in impulse turbine. With national development of western regions implementation, for development western high water head resource of water power, to the impulse turbine, especially Pelton turbine, the research in numerical calculating seems extremely urgent.Based on large-scale pelton turbine of YeLe water power station in SiChuan province, establishment N-S equation and k-e model;control equations were dealt with by means of finite volume scheme, first-order upwind scheme, implicit model;made a discretization using SIMPLEC algorithm.Thus, the following results can be achieved with the numerical simulation on three dimensional steady incompressible turbulent flow fields.This paper receives these points achievements after numerical simulation:1 、 Study the energy loss rule of distributor with the different flows. Under normal discharge, the loss of head enlarges gradually, which attain the most when the water flows through 5th outlet, is 3.43m. And the loss of 6th outlet drops approximately 0.48m. The average loss of distributor reducts as the flow reduces. The loss with 0.5 time of normal discharge attains 24.4% approximately of with normal discharge. The loss with 0.75 time of normal discharge attains 50% approximately of with normal discharge.According to actual operating conditions of the power plant, the simulation with the different combination plans of 6 outlets is be done. Through comparing, when only opening one outlet, the loss of 1th is the minimum, is 0.35m;when opening two outlets, the loss of 1th and 4th is the minimumc, is 0.44m;when opening four outlets, the loss of 1th,2th ,4th and 5th is the minimum, is 0.9m.2、 Study energy characteristic and flow characteristic of nozzle with different water heads, attain the rule of the flow changing with the different degree and water head. To gush out syringe needle and nozzle surface export to , Attain the curves of pressure distribution with different degrees and water head, and predict the area of cavitation changing with the different degree and water head.Change cone angle of nozzle, it is optimum whose cone angle a is 75° after comparing in energy, flow, pressure distribute. And propose optimizing the structure of nozzle, according to nozzle sectionarea change rule.3 n Study energy characteristic and flow characteristic of the entire flow channel. Compare with the result of numerical stimulation of distributor and nozzle, finding the difference of the loss in the distributor part is less 0.2%, and the difference of the loss in the nozzle part is 2% approximately. It is proved that the numerical simulation of each part alone can meet the need of dependability, which also can save calculating resources.
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