Hydraulics analysis of filling and emptying system for evaluating the impact of water level variation on downstream of ship locks

To improve hydraulic analysis of filling and emptying system of ship locks that are located in strong tidal areas, a new hydraulic calculation method was developed. This method is based on the theoretical principles of ship lock's filling and emptying, considering the significant variation of water levels downstream of ship locks. This new hydraulic calculation method was used to analyze the Sanbao ship lock in Zhejiang province China, and evaluated the sensitivity of three factors:chamber area, initial water head, descending rate of downstream water level. The results showed that, when comparing to the analysis on constant water levels, the new calculation method revealed shorter filling time, lower peak flow and energy ratio. This study indicates that the new method can provide an appropriate evaluation of filling and emptying system on the impact of water level variation on downstream of ship locks. Findings from this study can be used to support technical design and operation of ship locks in strong tidal sea and estuary.