普兰店湾水体交换数值模拟研究

Numerical study of water exchange in the Pulandian bay

采用不规则三角网格和有限体积方法,建立普兰店湾附近海域的潮流数值模型,在验证良好的潮流数学模型的基础上,以溶解态的保守物质作为示踪剂,对普兰店湾水交换状况进行了数值模拟,将普兰店湾划分成6个区域,针对各区域进行了水交换能力研究。结果表明:普兰店湾内不同区域的地形和地理位置变化较大,水体交换能力平面分布不均匀。在普兰店湾的6个子区域中与湾外的水交换速度最快的为A区(湾口处),连续潮作用10 d后,水体交换率达到45%。水交换速度最慢的为F区,100 d后水体交换速率为14%。普兰店湾内水交换控制机制的区域性差异使得湾内不同区域水交换率相差较大。

Based on an unstructured grid, finite-volume coastal ocean model, numerical simulation model of tide and tidal current in the Pulandian bay is built. Based on a well-verified tidal flow mathematical model, the Pulandian bay is divieled into six areas, the dissolved conservative materials are used as tracers, an advection-diffusion water exchange numerical model is established. The water exchange ability of each area is studied. The results show that, there are great differences in water change abilities of different areas because of large topography differences of different areas in the Pulandian bay, of which, the horizontal distribution is extremely uneven for the exchange capacity of water re- sources in the Pulandian bay. Among the six regions of the Pulandian bay, water exchange in Region A （ the mouth of the bay） is the fastest,which has an exchange rate of 45% in 10 d,while the slowest Region is F. The water exchange rate is only 14%. The reason for relatively great difference in regional exchange rate in the Pulandian bay is compara- tively large regional difference in the exchange control mechanism.