Influence of Penstock Outlet Diameter and Flat Blade Lateral Twist Angle on the Performance of A Simplified Pico Hydropower System

A study to investigate the influence of penstock outlet and the flat blade lateral twist angle on the performance of an existing Pico-hydro system was undertaken. Five penstock reduced from76.2 mm to 15, 17.5, 20, 22.5 and 25 mm diameters at the outlet and a runner with adjustable flat blades were fabricated from mild steel sheet. For each of the penstock outlets, five blade twist angles of 50, 55, 60, 75 and 90-° were tested and the turbine and alternator speed measured with tachometer. The initial and final levels of water in the overhead tank as well as the periods of tests were also measured. The data collected was used to compute the flow rate and power for each set. A maximum computed power of 5600 W was obtained with the 25 mm penstock outlet in conjunction with the blade twist angle of 75o. Also, the maximum speed 1180 rpm of the alternator shaft was obtained for a penstock outlet diameter of about 20.25 mm at the same twist angle of 75o. These results imply that for the system potentially could generate appreciable power using flat blades with the penstock outlets and blade twist angles in the ranges > 20 mm and = 600 respectively. Considering the simplicity of the flat blade configuration, the results indicate good promise for providing relatively cheap, clean and convenient domestic power with further work on the system. Daniel T. Ipilakyaa | Alex O. Edeoja | Aondohemen Kulugh"Influence of Penstock Outlet Diameter and Flat Blade Lateral Twist Angle on the Performance of A Simplified Pico Hydropower System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-5 , August 2017, URL: http://www.ijtsrd.com/papers/ijtsrd2322.pdf http://www.ijtsrd.com/engineering/mechanical-engineering/2322/influence-of-penstock-outlet-diameter-and-flat-blade-lateral-twist-angle-on-the-performance-of-a-simplified-pico-hydropower-system/daniel-t-ipilakyaa