CFD Analysis on the Flat Runner Blades of Propeller’s Turbine under Low Head and Low Flow Condition

Abstract

Hydropower is one of the most widely source to produce electricity for domestic houses as well as for industries around the world. However, for those off-grid settlements the pico-hydro scheme is more suitable due to its cost-effectiveness (less maintenance), clean, user-friendly and do not involved with huge construction works. Even the installation of this type of hydropower scheme is very simple as do it yourself (DIY) concept. One of the most popular pico-hydro turbines which have been implemented widely in rural areas until nowadays is propeller type or also known as axial turbine. Propeller turbine is selected because it is suitable to operate under low head with high flow rate condition. However, in this particular case, low head with low flow rate of water are the two main parameters which need to be considered. This is because during dry or drought season the water level of the rivers will become low and fluctuated, and this scenario affected the performance of the propeller turbine itself. In order to overcome this problem, the runner blades of the propeller turbine need to be redesigned to suit with this nature behavior. Therefore, in this study the runner blades with flat profile with few different angles and number of blades will be applied under 2 meters head. On the other hand, since the low flow is another parameter which needs to be focused therefore the value of the water flow rate has been set to 13 l/s. Analysis tools such as Computer Fluid Dynamic (CFD) is applied in this study in order to determine the most optimum results based from few selected parameters which has been mentioned. From the CFD’s final result, 3 blades with angle 300 was the best combination among the parameters involved.