To the problem of normalized congestion of ships passing through locks with limited capacity in areas with busy water transportation in plain river networks,this paper is based on Yuxi double-line ship lock project to carry out a model study on the operating conditions for navigable open-gate mode.A two-dimensional hydrodynamic numerical model is used to research the influence law of key influencing factors,such as the difference in water level,the operation mode of ship locks,and the operation mode of the regulation lock on the water flow conditions for navigable open-gate mode.The test results show that the control node for water flow conditions during open-gate operation is located at the upper gate head.The reasonable operating water level difference for the navigable open-gate mode of the Yuxi Hub double-line ship lock should not exceed 20 cm.The formation time of the open-gate operational conditions is related to the operation mode of the ship lock.The larger the scale of the ship lock and the more lines it has,the shorter the creation time,which generally takes about 30 min.Under the premise of a certain water level difference,the combined operation mode of using multi-line locks and control gates can effectively improve the water flow conditions during open-gate operation and reduce the water flow velocity in the lock by more than 50%.The research results can be used as a reference for similar ship lock projects that plan to use the method of navigable open-gate mode to improve throughput capacity.