风在水库网箱养鱼水质影响中的数值模拟

根据天然水库的地形条件,结合某水库网箱养鱼带周围的水质监测,构建了有风条件下水库流场数值计算模型.在此基础上,对不同风速下该水库网箱带对周边水域水质浓度变化进行模拟.计算结果表明,同等条件下,自然风速小于7.5 m/s时,与无风时差异甚小;自然风速等于8.5 m/s时,粪大肠菌群、DO和BOD5有效横向衰减系数分别增大0.0016,0.0017和0.0032,影响范围分别扩大22.62%,19.50%和18.67%.进一步证实了风成流的形成对水库生态环境的影响.

Numerical simulation of wind's influence on water quality of reservoir with net tank fish culture

According to the natural topographic conditions of reservoir, combined with water quality monitoring for a reservoir area with net tank fish culture, a numerical calculating model was established for the reservoir flow field under windy condition. The variation of water quality density with change of wind velocity is also simulated for the water body with net tank. As demonstrated by the calculation results, under the same conditions, the water quality changes little when the natural wind velocity is less than 7.5m/s; when the natural wind velocity is up to 8.5m/s, the effective transverse attenuation coefficient of coliform, DO and BOD5 respectively increase by 0.0016, 0,0017 and 0.0032, and the influenced scope expand by 22.62%, 19.5% and 18.67% respectively. The influence of aeolic flow on the ecological environment of reservoir is further confirmed.