Session
Session 5 2022
Start Date
10-27-2022 12:00 AM
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Sinha P.K., Kumar, B., and Ahmad, Z. (2022). "Hydraulic Performance of Piano Key Weir with Linear and Curvilinear Profiles of Outlet Keys" in "9th IAHR International Symposium on Hydraulic Structures (9th ISHS)". Proceedings of the 9th IAHR International Symposium on Hydraulic Structures – 9th ISHS, 24-27 October 2022, IIT Roorkee, Roorkee, India. Palermo, Ahmad, Crookston, and Erpicum Editors. Utah State University, Logan, Utah, USA, 10 pages (DOI: 10.26077/d163-390d) (ISBN: 978-1-958416-07-5).
Abstract
With rising demand for storing water in reservoirs, many spillways require modification by optimizing their shape for enhancing their discharge capacity. A Piano Key Weir (PK weir) is a modified weir and it is installed at the dams to augment the discharge capacity of the weir. Due to different geometrical configurations of PK weirs, the hydraulic performance of the weir is still in evolving research. In this study, hydraulic performance of two different models of PK weir is studied experimentally. All the configurations of both the PK weir are same except the shape of the outlet keys. The outlet key of the first model is linear whereas for the second model a curvilinear ogee shape is adopted. Ten discharges between 0.0075-0.03 m3/s and ratio of head over crest to weir height between 0.17-0.58 m were considered for each model. Water surface profiles were plotted along longitudinal and transverse directions at various sections of the PK weir. The effect of the weir geometry on discharging capacity was studied and it is found that the PK weir with curvilinear shaped outlet key is hydraulically more efficient than the linear shaped key. The coefficient of discharge of PK weir with curvilinear shaped outlet key is 12.41-18.15% more than the linear shaped key.
Hydraulic Performance of Piano Key Weir with Linear and Curvilinear Profiles of Outlet Keys
With rising demand for storing water in reservoirs, many spillways require modification by optimizing their shape for enhancing their discharge capacity. A Piano Key Weir (PK weir) is a modified weir and it is installed at the dams to augment the discharge capacity of the weir. Due to different geometrical configurations of PK weirs, the hydraulic performance of the weir is still in evolving research. In this study, hydraulic performance of two different models of PK weir is studied experimentally. All the configurations of both the PK weir are same except the shape of the outlet keys. The outlet key of the first model is linear whereas for the second model a curvilinear ogee shape is adopted. Ten discharges between 0.0075-0.03 m3/s and ratio of head over crest to weir height between 0.17-0.58 m were considered for each model. Water surface profiles were plotted along longitudinal and transverse directions at various sections of the PK weir. The effect of the weir geometry on discharging capacity was studied and it is found that the PK weir with curvilinear shaped outlet key is hydraulically more efficient than the linear shaped key. The coefficient of discharge of PK weir with curvilinear shaped outlet key is 12.41-18.15% more than the linear shaped key.