Search published articles


Showing 2 results for Experimental Investigation
Experimental Study of Discharge Coefficient at the Dentate Trapezoidal Labyrinth Weir
J. Meshkavati Toroujeni, A.a. Dehghani, A. ٍemadi, M. Masoudian,
Volume 25, Issue 3 (12-2021)
Abstract
One of the crucial problems that exist in the irrigation networks is the fluctuation of the water surface flow in the main channel and changes in the flow rate of the intake structure. One of the effective methods to decrease these fluctuations is increasing the weir crest length at the given width of the channel with the use of the labyrinth weirs can be achieved for this purpose. The labyrinth weir is the same linear weir that is seen as broken in the plan view. In this study, a labyrinth weir with a length of 3.72 m, three different heights of 15, 17, and 20 cm, three different shapes of dentate (rectangular, triangular, and trapezoidal), and a linear weir were used in a recirculating flume with 15 m length and 1 m width. The result showed that for a given length and height of weir, with the increasing of the upstream water head to the weir height ratio (), the discharge coefficient decreases. The results showed that by increasing weir height, the discharge coefficient decreases for a given length of the weir. Linear weir and labyrinth weir without dentate create more water depth at the upstream by 3.3 and 1.2 fold compared with dentate labyrinth weir.

Experimental Investigation of Local Scour Downstream of a Type B Piano Key Weir on Sand and Gravel Bed Materials
L. Babakhah, A. Khoshfetrat, E. Delavari,
Volume 29, Issue 1 (4-2025)
Abstract
Piano key weirs are a new form of labyrinth weirs and exhibit nonlinear characteristics. Due to their high efficiency regarding flow capacity, it is crucial to investigate local scour and identify solutions to mitigate it. Local scour was examined downstream of a trapezoidal piano key weir type B for the first time in this study. The weir was installed 5.50 m from the start of the channel and has a height of 0.20 m, featuring three cycles (three outlet keys, two inlet keys, and two inlet half keys). Three tailwater depths and three different flow rates were also utilized. The maximum scour depth increases with a higher densimetric Froude number and flow rate while decreasing with tailwater depth. The range of the dimensionless parameter for the densimetric Froude number in this study varies between 1 and 2. Additionally, sand and gravel were employed as two types of bed materials. As the diameter of the bed material increases, the maximum scour depth decreases. The scour index for gravel bed material is significantly lower than that for sand material, indicating that the risk of weir overturning is much lower in gravel bed material.

Page 1 from 1     

© 2025 CC BY-NC 4.0 | Journal of Water and Soil Science

Designed & Developed by: Yektaweb