Rotating Disc Apparatus and its application to estimate sediment erosion in Hydro turbines

Abstract

The removal of surface material due to repeated impacts of sediment is known as sediment erosion. This prominent phenomenon is found to exist on a run of the river types of hydro projects where the hydro turbines are exposed to sediment particles. It has drawn the attention of researchers, academic institutions, and hydropower developers to conduct research on this issue. Investigation of the problem at the site may require sophisticated equipment and sensors- set up for quantitative measurements. This process is time consuming and difficult as it is difficult to access the erosion location. Laboratory setup can be a solution to study and investigate erosion behaviour in well-controlled laboratory conditions. Among several erosion testing apparatuses, Rotating Disc Apparatus (RDA) has been used for the investigation of erosion as well as cavitation of hydro components, and to study the erosion resistivity of different materials. This device mainly consists of a rotating disc and an electric motor, which is used to rotate a disc-holding specimen. This paper evaluates the RDA for its applicability in simulating the flow on the surfaces of the components of the hydro turbines as that occurs in actual hydro power plants. The outcomes from the present study indicated that RDA produces promising erosion results and can simulate the wear conditions.