Abstract:

The waterway between Three Gorges Dam (TGD) and Gezhouba Dam is tortuous and varied. The unsteady flow caused by the discharge and daily regulation of TGD powerplant complicates the navigation conditions between the two dams. We established a 3-D mathematical model to simulate the unsteady flow caused by the operation of power units. By analyzing the calculation results, we obtained the variation regularity of water surface water gradient and surface water velocity in typical segment between the two dams in the presence of different operation time s and discharges. Results show that with the shortening of the operation time of power units, the increment of surface water gradient in the most hazardous segment intensified, and the maximum surface velocity increased linearly; while with the increase of discharge, the surface water gradient and maximum surface velocity increased linearly.

Key words: waterway between Three Gorges dam and Gezhouba dam, flow variation, navigable flow condition, 3D mathematical model