枸杞岛养殖海域流场环境改造的数值模拟

A numerical simulation of environment improvementin the aquaculture sea area of Gouqi Island

为造成适合于网箱养鱼的流场环境,同时扩大贻贝和藻类养殖面积,拟在枸杞岛西侧海域建设堤坝工程,通过数值实验对工程前后的流场变化进行了模拟。数值模型采用半隐式有限差分格式,经离散处理后,模型最后用迭代法求解一个五点方程。计算结果显示,模拟流场与枸杞岛周围海域实际流场吻合、精度良好。在此基础上,对两个不同的建坝方案分别进行数值计算,预演、比较堤坝工程实施前后海域流场的变化,从中选择既满足南侧海域深水网箱养殖的低流速要求,又可以尽量增加北侧海域贝类、藻类养殖面积的较佳方案。

To develop cage aquaculture, expand the aquaculture area of mussle and algae, and improve the environment, a dam to decrease the current velocity is planned to be built near Gouqi Island. In this paper, the semiimplicit finite difference scheme presented by V. Casulli is applied to a tidal current field numerical model that accords with observed data around the Gouqi Island sea area in the case of before the project. On this basis, two project schemes are produced. Through numerical computation the velocity variety before and after the project is previewed and compared. Finally, the better project scheme that agrees with the low velocity of the southern cage culture sea area and the larger aquaculture area of the northern seashell and algae culture sea area is selected.