Influence on Performance of Radial Straight Blade Hydraulic Turbine in Different Meridional Flow Channel.

In this paper, the influence on performance of radial straight blade hydraulic turbine is studied with radial meridional flow channel and mixed-flow meridional flow channel. Firstly, the theoretical models are suggested for radial straight blade hydraulic turbine. Secondly, runners are designed based on two different types of meridional flow channels. Finally, the numerical simulation is carried out for different schemes, while the performance and flow field are analyzed and compared. Results show that the two different schemes adapt to ultra-small discharge and head with large fluctuation. Moreover, the best numerical predicted efficiency is 81.4% for radial straight blade hydraulic turbine with the mixed-flow meridional flow channel, which is 1.8% more than the radial meridional flow channel. Meanwhile, with a larger conveyance capacity, the optimal efficiency is verified for the hydraulic turbine with mixed-flow meridional channel, and it can meet the needs of hydraulic energy recovery with ultra-small discharge. The conclusions serve as a reference in the design of hydraulic energy recovery turbine. [ABSTRACT FROM AUTHOR]