WANG Zhigang, ZHANG Dong, ZHANG Hongwei, ZHANG Rui

Department of Hydraulics, IWHR, Beijing 100038, China

Abstract: The baffles are the key structure of the baffle-drop shafts. With the help of physical model tests, the flow patterns in the baffle-drop shafts were tested, and the functions of the baffles with its designing considerations were analyzed. The results were shown as follows: the top baffle was designed for carrying and adjusting inflow, then making it flow down to the second baffle naturally. The distance between the top baffle and the shaft inlet was the chief factor which influences the top baffle arrangement and its too large evaluating could make the flow strike on the central dividing wall or the second baffle directly. The main baffles lying between the top baffle and the bottom water surface were designed for energy dissipation. Baffle spacing would be the chief influence factor; being too large would reduce energy dissipation while being too small would influence the flow capacity. The functions of underwater baffles were energy dissipation and de-aeration. According to the test results, 2~3 baffles could meet the requirements.

Key words: baffle function; physical model test; baffle-drop shaft; engineering hydraulics

Published in: Journal of China Institute of Water Resources and Hydropower Research, Vol. 13, No. 4, August 2015