Pressure pulsation reduction in the draft tube of pump turbine in turbine mode based on optimization design of runner blade trailing edge profile

Reversible pump turbine plays an important role in pumped storage technology. Its pressure pulsation perfor-mance also directly affects the stability and efficiency of unit operation. In this paper, under the conditions of multiple guide vane openings and multiple heads for a pump-turbine unit, based on the reasonable runner blade geometric deconstruction, a parameter control method of runner blade trailing edge is proposed. The Genetic Algorithm combined with Fuzzy Logic (GA-FL) is used as the optimization strategy. After optimization iteration, the optimized runner blade trailing edge shape corresponding to minimum value of pressure pulsation intensity is obtained. In addition, numerical simulation calculation and test verification are carried out for the initial and optimized units, the results are all in good agreement. The results show that the unit efficiency is slightly improved and the relative pressure pulsation intensity in draft tube is significantly reduced. Especially in the case of small guide vane opening, the pressure pulsation performance of optimized unit meets the actual engineering standards.

Automated summary

This paper proposes an optimization method for reversible pump turbines, which achieves the minimum pressure pulsation by reconstructing the runner blade geometry and using the Genetic Algorithm combined with Fuzzy Logic. Numerical simulation and experimental verification show that the optimized unit has slightly improved efficiency and significantly reduced pressure pulsation intensity in the draft tube. Especially at small guide vane openings, the pressure pulsation performance of the optimized unit meets the actual engineering standards.