Experimental and Numerical Analysis of Energy Dissipation in Piano Key Weirs with Stepped and Baffled Barriers at Downstream Slop

Document Type : Research Paper


1 1. Department of Water Science Engineering, Khouzestan Science and Research Branch, Islamic Azad University, Ahvaz, Iran. 2. Department of Water Science Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.

2 Department of Water Science Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.

3 Department of Water Science Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran


Piano Key Weirs (PKWs) are amongst the newly developed long-crested weirs that offer a higher discharge capacity relying on their more extended crest compared to labyrinth weirs of the same width. However, the use of barriers at the outlet of PKWs to increase energy dissipation has received little attention so far. In the present work, stepped and baffled models (with a bench height of 30 mm and baffle dimensions of 30 * 30 mm) were adopted to conduct experiments, and the Flow3D software was used for 3D simulation. Experiments were performed using discharge rate of 10 to 50 lit/s. The results revealed by increasing the discharge rate, the energy dissipation reduces. The energy dissipation rate using the baffles was 8.75% higher than that of the stepped model, and 15.21% higher than that of the case with no barriers.


Main Subjects

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