洪水入海对养殖环境影响的数值分析

Numerical analysis of the effect on the floodwater of Yalujiang on the aquatics in the northern Yellow Sea

基于三维流体动力学和热力学原始方程 ,采用σ坐标变换技术 ,建立了三维斜压场数值模型。模型采用ADI格式求解连续方程和动量方程 ,采用FS法和TVD格式求解各标量方程 ,从而使模型的精度提高到二阶 ,并且节省运算时间。利用建立的三维斜压场数值模型 ,对鸭绿江洪水期形成的低盐水体的分布进行了数值模拟 ,进而分析了鸭绿江洪水入海对黄海北部海域的海水养殖业的可能影响。鸭绿江特大泄洪形成的超低盐混浊水体入侵 ,是筏养扇贝致死的主要原因。及时预报大洪水影响下的低盐水体分布 ,可有效地防止洪水污损灾害。

Based on the three dimensional hydrodynamic and thermodynamic primary equations with the σ coordinate transformation, a three dimensional baroclinic numerical model was developed. The continuity and momentum equations were solved using the alternative directional implicit method, and the scalar equations were solved using the fractional step technique, so that the precision of the model was up to second order and the running time of the model can be saved. The distribution of the low salinity water due to the runoff of Yalujiang river during the period of flooding was simulated numerically. The possible effect of the floodwater of Yalujiang on the aquatics in the northern Yellow sea was analysed. The main death reason of aquatics shellfish is due to the intrusion of the extra low salinity turbid water formed by the big flood from Yalujiang. The prediction of the distribution of low salinity water under a big flood could prevent the calamity of flood.