Investigating the discharge characteristics over a piano key weir with varying key slope and key width ratios under varying discharges
Year: 2025
Type: article
Abstract: The objective of the present study was to investigate the effect of inlet to outlet key slope ratios ( S i / S o ), inlet to outlet key width ratios ( W i / W o ) and head over the weir on the coefficient of discharge ( C pkw ) of type-A trapezoidal piano key weir (TPKW). It was observed that the C pkw of TPKW was found to be decreased as the S i / S o ratio reduced. The percentage of reduction in C pkw was found to be 18.5%, 16%, 13.7%, 9.4%, 6.3%, and 3% at S i / S o = 0.60, 0.75, 0.80, 1.00, 1.25, and 1.33, respectively in comparison with the S i /S o = 1.67. As far as the effect of W i / W o ratio on the C pkw of TPKW is concerned, the C pkw of TPKW was observed to be increased with increasing W i / W o ratios. Moreover, the C pkw at W i / W o = 1.32 and W i / W o = 1.15 was found to be 9.4% and 7.5% higher than W i / W o =1 respectively, while for the case of W i / W o = 0.76, its value was found to be 3.3% lower than W i / W o = 1. Furthermore, the hydraulic efficiency of TPKW was found to be decreased as head over the weir increased. The maximum value of C pkw of TPKW was observed to be 3.2 corresponding to lowest h / P ratio for the model having S i / S o = 1.67 and W i / W o = 1.32, while the minimum value of C pkw of TPKW was found to be 1.58 corresponding to highest h / P ratio for the model having S i / S o = 0.60 and W i / W o = 0.76. Additionally, sensitivity analysis results revealed that the C pkw of TPKW is more sensitive with h/P ratio than other ratios.
Authors: Mujahid Iqbal, Usman Ghani
Institution: University of Engineering and Technology Taxila
Language: English
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4408217959