Evaluation and Analysis of Flow over Arced Weirs Using Traditional and Response Surface Methodologies

Abstract

This paper experimentally studies the hydraulic characteristics of arced weirs located in a reservoir. The accuracy and ability of the response surface methodology (RSM), especially central composite design (CCD), to describe the hydraulic performance of this type of weir is validated using experimental data. The discharge coefficient of arced weirs is presented as a function of headwater ratio (Ho/P) and magnification ratio (L/W) using both traditional and response surface methodologies. The results indicate that like the traditional methodology, RSM-CCD introduces an acceptable model to determine the discharge coefficient of the arced weirs, but it requires a much lower number of experiments. The results show that the discharge coefficient of an arced weir decreases by increasing Ho/P and L/W [or arc angle (Θ)]. In addition, compared to a linear weir, the efficiency of an arced weir can increase up to 50%. Finally, based on the experimental results, a method is introduced for designing the in-reservoir arced weirs.