연직수문의 자유방출흐름에서 수축단면과 에너지손실을 고려한 최적 유량계수

Abstract

Sluice gates are hydraulic structures frequently installed in rivers and dams for control of flow discharge and water level. Accurately estimating the flow rate (or discharge coefficient) discharged through the gate is a very important issue for water resource management. Most existing studies on discharge coefficient include the assumption that the contraction coefficient downstream flow of the gate remains constant and ignores energy loss. In this study, a discharge coefficient of free flow past a sluice gate was proposed that considered the vena-contracta and energy loss. First, when energy loss was ignored, the best discharge coefficient estimation result was obtained using the constant contraction coefficient value of 0.611. Also, when energy loss was considered, the best discharge coefficient estimation result was obtained when a variable contraction coefficient was used rather than a constant value. For use in estimating the discharge coefficient, the contraction coefficient and energy loss coefficient were presented as regression equations.