Author(s): Shoji Yamashita; Yasuyuki Shimizu; Kohji Hohjo
Linked Author(s): Yasuyuki Shimizu
Keywords: No Keywords
Abstract: Most of the rivers in Hokkaido, Japan, are covered with the ice during the winter. Therefore, the accurate discharge measurement in the ice-covered river is very important in the river management works. Theoretical understanding of the velocity distribution is also needed to improve the accuracy of discharge measurements. The velocity profile is a function of the boundary shear stress which is proportional to several factors such as slope, water depth, gravity and density. In the open channel flow, the wetted perimeter, on which the boundary shear stress acts, is composed of channel bed and banks, while another boundary is added between water and ice in the icecovered river. The roughness of ice-water boundary is different from the bed roughness, which makes it difficull to understand the flow structure under the ice. In order to predict the velocity profile and boundary shear stress in ice-covered flows, a practical two-dimensional model is proposed. The model is verified using an experimental data obtained using a straight flume covered with a board which represents the water surface Ice.
Year: 1992