Experimental Evaluation on Performance of Novel Cross-flow Impulse Turbine for Water Stream in Hilly Areas of Pakistan

Abstract

Hydropower plants play a key role in power sector. Pakistan is facing an acute energy crisis due to dependence on fossil fuels having economical as well as environmental consequences. Now-a-days, small hydropower is important in Pakistan due to its simplicity, efficiency and availability of hydro potential in this region. The present work includes designing of cross flow turbine and evaluating its performance parameters like tip speed ratio λ, power coefficient C p and constraints affected by inlet guide vane angle. The prototype is tested for different guide vane angle; that is 20.5°,25.5°,30.5°,35.5°,40.5° to find maximum efficiency of cross-flow turbine. Power coefficients C p for cross-flow turbine are calculated for different inlet guide vane angle and tip-speed ratios (TSR . This cross flow turbine has been designed for low head of 6 meter which would have theoretically generated the electricity of 10 kW. The experimental setup is tested at the hilly waterfalls region and its experimental and theoretical results are compared. The cross-flow turbine is capable of producing 8.9 kW electric power at the head of 6 m, flow rate of 0.21m 3 /s and channel flow speed is 10.84 m/s. The optimum efficiency of 89% is achieved when C p is 0.78 and TSR reaches 4.4 at the middle position when guide vane angle is 30.5 o .