Abstract
In the hydropower plants exposed to excessive sediment concentration, the components of Francis turbines, especially the regions of Guide Vanes (GVs) and Runner Vanes (RVs) are severely eroded. The side-wall clearance between GV and runner is present in these turbines to separate the rotating and stationary components. The height difference between the runner inlet and GV outlet covers, introduced during the fabrication or assembly process might play a crucial role in accelerating the erosion process in these components. This study is focused on numerical analysis of simplified geometries that replicate different scenarios of the height difference and consequent flow behaviour in the side-wall clearance of Francis turbines. The numerical analysis is done in OpenFOAM using the available solver adopting the finite volume method (FVM). The numerical study is compared with the experimental results obtained from Rotating Disc Apparatus (RDA). The numerical analysis shows the vortex formation in the side-wall clearance region which traps the sediment particles. Such vortex formation causes erosion in the region. The vortex formation and flow behaviour in different height difference scenarios vary with each other and so does the erosion pattern in the experimental results.
Published Version (Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: IOP Conference Series: Materials Science and Engineering
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.