Effect of Pitch Angle to Shear Stresses on The Runner Blade Surface Using Computational Fluid Dynamics (CFD)
Pribadyo, P (a,c*), Hadiyanto, H(a), and Jamari, J(b)

a) Doctoral Program of Environmental Science, School of Postgraduate Studies, Diponegoro University, Semarang, Indonesia
* dyo_1806[at]yahoo.co.id,
b) Department of Mechanical Engineering, Faculty of Engineering, Diponegoro University, Semarang, Indonesia
c) Faculty of Engineering, Teuku Umar University, Meulaboh, 23615, Indonesia

Abstract

The main aspect of each hydroelectric power station for a low head is a turbine that is capable of producing electricity with maximum power through the shaft rotation. Because turbine blades are the main component of propeller turbines that are directly connected to the shaft and connected with generators, for that we need special attention that must be understood in the design of turbine blades so that performance becomes more optimal. Propeller turbine performance can be improved by changing the turbine design parameters. One method developed is to vary the blade angle on the runner blades. Analysis of the influence of the blade on propeller turbine performance is done through numerical simulations based on Computational Fluid Dynamics. Simulations are carried out with a variation of propeller turbine blade angle of 25 degrees, 30 degrees, and 35 degrees at flow rates between 0.08 to 0.5 m/s. Simulation results show shear stress distribution that occurs in the blade tends to always increase with an increase that is not linear. Blade angle of 30 degrees at maximum flow rates have the best performance compared to turbine blades 25 degrees and 35 degrees. These conditions indicate that the magnitude of the angle does not significantly affect the shear stress that occurs.

Keywords: Pitch angle, shear stresses, runner blade, simulation, CFD

Topic: Mechanical Engineering