Computational Study on the Effect of Anti-Vortex Blades and Stepped Chambers in Morning Glory Spillways
الموضوعات :
1 - گروه مهندسی عمران، واحد سپیدان، دانشگاه آزاد اسلامی، سپیدان، ایران
الکلمات المفتاحية: Shaft Spillway, Vortex breaker, Flow, Stepped Chamber, Comsol soft ware. ,
ملخص المقالة :
Shaft spillways are a specialized category of circular spillways primarily used to release unexpected floodwaters from both earth and concrete dams, playing a vital role in flood management. Among the various types of shaft spillways, stepped and smooth spillways stand out as particularly significant and widely adopted designs. Notably, stepped spillways offer a considerably higher flow discharge capacity compared to smooth spillways, underscoring the importance of understanding their complex flow behavior to optimize performance and enhance efficiency in real-world applications. Additionally, the integration of vortex breakers has been shown to significantly influence the flow dynamics within shaft spillways, necessitating careful consideration during design and operational planning. To ensure efficient operation, it is crucial to minimize the risk of cavitation—a phenomenon where flow pressure drops below the fluid vapor pressure, potentially causing severe structural damage to the spillway.
This research aims to investigate the cavitation index associated with smooth shaft spillways while conducting a comparative analysis with a specific type of stepped spillway, contributing valuable insights to the existing knowledge base. The study comprehensively examines how variations in flow regimes impact spillway performance, including changes in step dimensions and discharge characteristics. Two distinct spillway models—a smooth spillway and a stepped spillway—were utilized, each equipped with three different vortex breaker configurations, enabling a detailed assessment of hydraulic flow characteristics and cavitation risks. Systematic measurements of pressure and flow velocity were recorded at multiple points along the spillway surface for each experimental run, focusing on the inlet discharge.
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