런너교체 전후 프란시스 수차성능의 실험적 고찰

In order to improve the efficiency, the CFD-based design system is applied to the Francis turbine replacement project with Korea Fluid Machinery Association (below KFMA) and K-water. The inversed design technique and the fully turbulent 3-dimensional flow simulations are performed in the previous study. In this study, the runner is newly manufactured from the reversed engineering and CFD's results. By Manufacturing method, the precision wood pattern, casting, a number of the surface blasting as like the buffering and a balancing technique is selected Furthermore, The turbine with newly runner is respectively experimented with the output in accordance with IEC60041 code. The performances of the new design are verified by the approved test and the guarantees have all been successfully met. From the experiment results, the efficiency of the newly turbine, 87.5% is more enhanced than the efficiency of the old model for the 500kW. The perfect combination of the CFD analysis has finally resulted in a new model which can provide about a 10% increase in peak efficiency.