在长江口北槽深水航道工程的背景下,以实测地形资料为基础,利用FVCOM,模拟南导堤越堤水流的时空变化.通过对越堤流过水断面通量的计算,分析工程前后越堤流的时空变化规律.导堤丁坝的修建,使得南北槽之间的水动力条件显著改变,工程之后,横向水流净通量指向北槽,且量值较大.越堤水流的沿程分布,以导堤转角为界,上半段逐渐减小,下半段逐渐增大,上半段净通量小于下半段;越堤流的净通量,在季节上变幅不大,在潮周期内呈周期性波动,净通量与潮位呈良好的线性相关.
A numerical model based on the insitu measured topographic data was implemented, using the unstructuredgrid, threedimensional primitive equation, finitevolume coastal ocean model (FVCOM) including a dikegroyne module, for the study of temporal and spatial variations of overtopping flow at the south leading jetty constructed in the deep waterway channel. We investigated the temporal and spatial changes of overtopping flow by computing crosssection water flux before and after the project. The hydrodynamic condition around the north passage showed noticeable changes after the building of dikes and groynes. After the construction, respectively, net lateral current between the two channels points to the north passage with a relatively large amount of discharge. As estimated, spatially varying unit width net overtopping water flux had a significant feature, which was bounded at the corner, showed that the flux increased gradually at the upper half and decreased at the latter with a larger value. On a time scale the amplitude appeared no remarkable changes seasonally but on the other hand paced periodically in a tidal cycle. Moreover, the results showed a strong linear correlation between net water flux and tidal level.
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