Dry season runner with optimized blade number and mixed-flow water turbine provided with runner

The invention discloses a dry season runner with an optimized blade number and a mixed-flow water turbine provided with the runner. The dry season runner with the optimized blade number comprises an upper crown, a lower ring, and a plurality of blades which are arranged between the upper crown and the lower ring and are distributed uniformly along the peripheral direction; Qk is the average flow rate in a dry season; Qr is the rated flow rate of the water turbine in a wet season; K is the ratio of the Qk to the Qr, namely K=Qk/Qr; Delta Zr is the difference value between the numbers of the blades of a wet season runner and the dry season runner; the Delta Zr is in negative correlation with the value K, namely the smaller the value K is, the greater the Delta Zr is. According to the dry season runner with the optimized blade number, the number of the blades on the runner which is suitable for a dry season is reduced, so that the excess flow of an optimal running area of the runner of the water turbine is greatly reduced, and the phenomenon that debris blockage among the blades of the runner appears frequently when the water turbine runs is avoided without reducing the opening degree of the outlet of the blades of the dry season runner compared with that of the wet season runner; meanwhile, the machining and manufacturing of the runner are facilitated, the friction resistance of water flow in the runner can also be reduced, and the hydraulic efficiency is favorable to improve.