摘要
建立了磨刀门河口二维水动力模型,在对现场实测资料验证良好的基础上,选取开挖中心拦门沙、东汊与西汊疏浚及导堤封堵东汊3个方案,比较了它们对排洪的影响,以探讨河口拦门沙的排洪效应问题。数值模拟表明,拦门沙开挖对磨刀门河口局部水动力特征的影响较小,拦门沙的开挖不能大幅增加洪水排泄的效率;修建导堤封堵东汊会加大挂定角至大井角的水面比降,造成更严重的壅水;东、西汊的浚深对排洪的影响也较小。拦门沙的存在看似对于泄洪有一定的阻碍作用,实际上河口及其拦门沙可以通过地貌形态的自动调整来与洪水径流作用相适应。
The Modaomen Estuary,which connect the complicated stream network of the Pearl River and the estuarine bays,is the most important water way in discharging freshwater and sediment into the estuarine bays. However,there is immense bar area evolved in the outer subaqueous delta. Consequently,the flood releasing safety is the most important issue in the regulation project of the estuary. A 2-D tidal flow numerical model is established to investigate the effects of different regulation measures on the flood release in the Modaomen Estuary,and the regulation measures include excavating a channel in the sand bar,obstructing the east channel and dredging in the east channel and the west channel. The results show that the measure of excavating a channel in the sand bar is not helpful to improving the efficiency of flood drainage. The measure of obstructing the east channel results in an increase in the water surface slope between Guadingjiao and Dajinjiao,which intensifies the water damming. The effect of channel dredging in the east channel and west channel on flood drainage is not obvious. All these results indicate that the sand bar does not have significant adverse impact on the flood drainage,which confirms the fact that the estuary sandbar system has its self-regulating effect to meet the need of flood drainage.
出处
《水利学报》
EI
CSCD
北大核心
2011年第11期1341-1348,共8页
Journal of Hydraulic Engineering
基金
广东省科技计划项目(2010A030200016)
国家自然科学基金(21077139)资助
关键词
磨刀门
拦门沙
排洪效应
数值模拟
modaomen estuary
sandbar
effect on flood drainage
tital flow numerical simulation
