Comparing discharge coefficient and water flow height of V-shape triangular weir crest in Flow-۳D software with an experimental model

Dam safety is the most important issue in the design, construction and operation of dams when it comes to dam construction, which is directly linked to the capacity of dam spillway. The water flowing over dam crest is considered one of the main causes of dam failure, as the insufficiency of weir capacity is one of the main causes of this phenomenon. Therefore, preventing damages caused by floodwater accounts for the chief reasons why weir is used in dam structure. Weirs are considered as key structures for controlling for flow conditions, measuring flow rate, and controlling flow depths in open channel. In this paper, by using Flow۳D software, we attempted to study the effect of four models of V-shape triangular weir and various heights of ۱۲, ۱۵, ۱۷.۵ and ۲۰ cm on discharge coefficient, flow depth in different cross sections, and difference of water depth on the weir relative to water depth in the upstream. Following this, the data derived from Flow۳D were compared with the results from an experimental model in order to ensure accuracy, in that relatively high similarity was observed between the experimental model and the software model.

Keywords:

weir , Flow۳d , triangular weir , flow depth , discharge coefficient.