Assessment of Construction Plan for Chungju Dam Supplementary Spillway Using Flow-3D Model

Abstract

The occurrence of extreme rainfall events is increasing owing to climate change. Therefore, projects to enhance the capacity of existing hydraulic structures are underway to address this challenge. In the case of the Chungju Dam, the installation of a supplementary spillway has been planned to accommodate the increased probability maximum flood. Hydraulic model experiments have been conducted for the design of large hydraulic structures. However, hydraulic model experiments have drawbacks, such as being time-consuming and costly, which make it challenging to consider various alternatives. Recently, with the advancement of computer technology, three-dimensional (3D) numerical models are replacing hydraulic model experiments. In this study, the suitability of the supplementary spillway installation plan for the Chungju Dam was evaluated using the Flow-3D model, and improvements were proposed. The proposed improvements include increasing the width of the spillway, shifting the location of the spillway downstream, and increasing the diameter of the tunnel. This study is expected to be a valuable reference for planning the Chungju Dam and applying various 3D numerical models.