温州瓯江口海域三维水沙计算

本区域(如图5.11)地处浙南沿海,温州瓯江口区域,地理位置为:北纬27°35′~28°09′,东经120°45′~121°30′。其北部有苍山、雁荡山、洞宫山等,对西北来的寒流起着屏障作用,且纬度较低,因此区域内秋季温暖,夏季凉爽,平均气温在17℃~18之间。

温州浅滩附近海区潮汐属正规半日潮。潮汐比值(瓯江口外洞头为0.3,河口附近的黄华为0.25)。一昼夜两潮,潮高不等,现象较为明显,一般春分~秋分间夜潮高于日潮,秋分至翌年春分间,夜潮低于日潮。且落潮历时大于涨潮历时,潮差大,是我国显著的强潮海区之一。

本次计算所依据的测量资料是由长江委水文局长江下游水文水资源勘测局对测区内连屿、坎门、大岩头、鹿西岛、小门岛、乌仙头、状元、洞头、黄华、海思、七里、龙湾和北麂岛共13个潮位测站,从200692902006101323进行连续15天的同步潮位观测所得。

模型将计算域划分为18958个节点,36434个三角形单元,为和所测实测资料进行对比,将计算域从200692902006101323进行数值模拟,共15360个小时,入流边界给定计算域内下边界及右边界上四点潮位过程,初始水位给定恒定水位1.85m。图5.12为计算域的计算网格剖分图,图5.135.16为给定已知边界上的四点潮位过程。

由于潮位测站较多,本验证选取龙湾站,黄华站,鹿栖岛站,坎门站,洞门站及北岛站上计算结果与实测潮位资料对比。结果如图5.175.22所示,由对比可以看出,计算潮位过程与实测资料吻合良好。

对流速和含沙量在107141081727个小时内进行模拟,此时处于大潮期,本模型采用悬沙模型,中值代表粒径为0.035m,泥沙干容重1400kg/m3,泥沙沉降速度0.11004cm/s,在不考虑冲淤地形的条件下进行模拟计算,将流速计算值与有实测资料的1#3#4#5#6#10#位置上近进行对比,对比结果如图5.235.28所示,对比可以看出吻合良好。含沙量计算结果与有实测资料的2#5#6#10#进行比较,结果如图5.295.32所示,从结果可以看出含沙量的过程符合实际测量的规律,可见该悬沙模型可以用来预测含沙量的分布过程。

5.11 模拟区域图

 

Fig. 5.11   The sketch map for computational domaint

 

5.12 维计算域网格示意图

Fig. 5.12   The sketch map for two-dimensional computational grid

 

5.13  1点潮位变化过程线

Fig. 5.13   The change process of tidal with time at point 1

 

5.14  2点潮位过程

Fig. 5.14  The change process of tidal with time at point 2

 

5.15  3点潮位过程

Fig. 5.15   The change process of tidal with time at point 3

 

5.16  4点潮位过程

Fig. 5.16  The change process of tidal with time at point 4

 

5.17  龙湾站潮位实测资料与计算对比

Fig. 5.17  The contrast of tide changes with time between computed result and measured at LongWan station

 

5.18  黄华站潮位实测资料与计算对比

Fig. 5.18  The contrast of tide changes with time between computed result and measured at HuangHua station

 

5.19  鹿栖岛站潮位实测资料与计算对比

Fig. 5.19  The contrast of tide changes with time between computed result and measured at LuXiDao station

 

5.20  坎门站潮位实测资料与计算对比

Fig. 5.20  The contrast of tide changes with time between computed result and measured at KanMen station

5.21  洞门站潮位实测资料与计算对比

Fig. 5.21  The contrast of tide changes with time between computed result and measured at DongMen station

5.22  岛站潮位实测资料与计算对比

Fig. 5.22  The contrast of tide changes with time between computed result and measured at BeiJiDao station

 

5.23  1#流速计算值与实测值对比

Fig. 5.23  The contrast of velocity changes with time between computed result and measured

at point 1#

5.24  3#流速计算值与实测值对比

Fig. 5.24  The contrast of velocity changes with time between computed result and measured

at point 3#

 

5.25  4#流速计算值与实测值对比

Fig. 5.25  The contrast of velocity changes with time between computed result and measured

at point 4#

5.26  5#流速计算值与实测值对比

Fig. 5.26  The contrast of velocity changes with time between computed result and measured

at point 5#

5.27  6#流速计算值与实测值对比

Fig. 5.27  The contrast of velocity changes with time between computed result and measured

at point 6#

 

5.28  10#流速计算值与实测值对比

Fig. 5.28  The contrast of velocity changes with time between computed result and measured

at point 10#

 

5.29   2#位置含沙量计算值与实测值对比

Fig. 5.29  The contrast of sediment concentration changes with time between computed result and measured at point 2#

 

5.30  5#位置含沙量计算值与实测值对比

Fig. 5.30  The contrast of sediment concentration changes with time between computed result and measured at point 5#

 

5.31  6#位置含沙量计算值与实测值对比

Fig. 5.31  The contrast of sediment concentration changes with time between computed result and measured at point 6#

 

5.32  10#位置含沙量计算值与实测值对比

Fig. 5.32  The contrast of sediment concentration changes with time between computed result and measured at point 10#