A micro Francis turbine for smart water meter self-generation: Study on the effects of structural parameters on turbine performance based on CFD simulations and experiments

With the popularization of smart water meters, the application of self-generation technology in the field of water meters has attracted much attention. Traditional smart water meters often require disposable battery power supply, which has problems such as battery power limitation and large workload of replacing batteries, and the replaced batteries will also cause pollution to the environment. In order to solve this problem, this paper proposed a micro Francis turbine applied to self-generation of smart water meters, and the effects of turbine structural parameters on turbine performance was investigated through computational fluid dynamics (CFD) and experiments. Through the theoretical design and optimization of the stay vane inlet angle and the blade numbers, the hydraulic turbine prototype for testing was obtained. After turbine performance tests, it was demonstrated that the micro Francis turbine was capable of generating a stable electrical energy output with acceptable water head reduction even at low water flow rates. Based on the verified numerical model, the effects of runner inlet width and runner outlet diameter on turbine performance are investigated by CFD simulation. The simulated results show that the optimized hydraulic turbine had an output power of 2.68 W and an efficiency of 70.1 %.