Numerical Simulation And The Method Of Parametric Mesh Generation Of Runner Gap

Along with the development of national economy, energy is a problem to be solved.In the draft agreement of renewable energy12th5-year program, hydropower capacitywill hit300million kw before2015.Hydropower production plays an important role inour country’s industry.With the capacity and size of hydropower units increase, and thecorresponding improving specific speed, the relative weakening of stiffness. The securityand stability of the operation has become paramount concern during the design,production, installation and production management of power station.The hydraulicstability of large Francis turbine related causes more complex. The reasons are morecomplex in a variety of power plant performance. We only research the turbine runnerclearance flow and axial thrust calculation in this paper.Axial hydraulic thrust of turbine runner not only affects the technical requirementsand economic indicators of the thrust bearing,but also the efficiency security andstability of hydropower units. When the upward force on the turbine is greater thangravity of hydropower units, the phenomenon of lifting hydropower units will happen;The downward axial force will improve the demand of design and manufacture of thethrust bearing. The error of traditional method using the model tests to predict realmachine hydraulic thrust is great. How to accurately calculate and predict the axialhydraulic thrust is important to ensure safety, stability,efficient operation of hydropowerunits. take advantage of numerical simulation techniques to simulate the turbine runnerclearance. Studying the flow of runner gap and predicting axial hydraulic thrust, whichprovide a theoretical basis for the design of runner clearance and thrust bearing.When taking CFD technology to simulate the flow of turbine runner clearance, meshgeneration accounts for most of all human time in a computing task. Therefore, the rapidability to quickly and accurately generate grid is an important issue. Gap geometry iscertain, so we can use the parametric approach to generate grid. The use of developedspecial parametric software allows analysts away from a large number of heavy andrepeated work such as creating geometry, mesh generation, which can greatly reduce thesimulation time, and will spare more time to take the analysis of results inpost-processing.