Effect of Flow Splitters on Energy Loss in C-Type Piano Key Weirs
DOI:
https://doi.org/10.31272/jeasd.3183Keywords:
Discharge Coefficient, Energy loss, Flow separation, Flow splitters, PKW, Type CAbstract
Piano key weirs (PKWs) are a new type of labyrinth weirs. They have a longer crest length within a limited width and, unlike linear weirs, ultimately have a higher discharge coefficient. The higher energy loss in PKWs can reduce scour. Therefore, this study used flow splitters on the weir crest and two C-type PKWs with heights of 0.18 m and 0.20 m. The splitters had rectangular and circular cross-sections. They were arranged in three configurations: two-by-two, four-by-four, and six-by-six in each cycle. The results showed that the presence of a flow splitter increases energy loss. Additionally, as the number of splitters increases, energy loss increases, and the discharge coefficient decreases. Adding six rectangular flow splitters to the weir per cycle resulted in an average increase in energy loss of approximately 10.40% and a decrease in the discharge coefficient of 18.60%. On average, rectangular flow splitters had 1.24% higher energy loss than circular ones. The energy loss in weirs with rectangular and circular flow splitters increased by about 6.89% and 5.72%, respectively, compared to those without flow splitters. A 10% increase in weir height led to a decrease in both the discharge coefficient (by about 9.20%) and the energy loss (by about 1.68%).
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Copyright (c) 2026 Amirhossein Fathi, Wadi Mohammed Wadi, Ali Khoshfetrat, Seyed Hamid Alavi (Author)
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