Retrofit Design Of Turbine Runner Based On CFD

In recent years, domestic CFD technology has a lot of application in turbine studty design aspects,and made a lot of achievements.For Computational Fluid Dynamics method and software was in-depth research and development, its reliability, accuracy, the calculation efficiency, computing visualization degree is greatly improved. The turbine 3d constant turbulent calculation based on the CFD,which make numerical test replaced model test for performance prediction become possible,and provide software platform for powerstation uprating-retrofitting,the components of turbine modified design. because of less investment, quick results,higher economic benefits are more and more attention And attention. Based on CFD in Hydraulic Turbine Equipment uprating-retrofitting have drawn more and more attentionGa kong power station of qinhai province is high head and low specific speed francis turbine. The occasion of this transform in the power plant,fistly,transformed its guide vane, high head low specific speed turbine distributor working in small opening,if using positive and symmetry airfoil guide vane, its head and imported water to form a Big incidence in opposite direction, Resulting in increased losses, so turned its head out into the negative curvature of the blade airfoil, it can well meet the import water. This paper through numerical tests verified various guide vane airfoils performance, from the numerical results, In the same optimum operating point, the units efficiency that negative curvature guide vane high positive curvature 3.14%.Secondly, the capacity increase, there is 2000KW Capacity margin around Ga Kong power station , the maximum output power of the original HLA606 runner was 10000KW,the relative height of guide vane b 0= 0.25, HL220-WJ-120 runner inlet diameter, the relative height of guide vane were equal to ga kong power station.So decided to replace the HLA606 runner with the HL220 runner.HL220 runner flow capacity greater than HLA606 runner,Ga Kong power station guide vane biggest opening which determined by the regulating ring and HL220 runner output close to 15000KW, that beyond the ga kong maximum load power of the generator, So have to transformation of reducing capacity of HL220 runner, Ga Kong Station actual parameters that bottom export and draft tube import diameter is 1.2m,This paper is cutting the trailing edge of HL220 blade Runner make the exit diameter be equal to 1.2m, at the same time in order to reducethe folw of runner,s capacity and increase 3 blades.Finally, numerical calculation shows, in the largest opening of guide vane,From the modified turbine of flow coponents inside the path line is smooth, steady flow,no deterioration of the flow field,The unit output is 12000KW,achieve expected purpose of uprating-retrofitting requirements.