大辽河感潮河段水体交换的数值研究

基于FVCOM建立大辽河感潮河段的水动力-扩散数值模型,采用保守物质输运扩散法研究大辽河感潮河段在潮和径流作用下的水体交换特征。结果表明:径流是影响大辽河感潮河段水交换的主要因素,径流为114 m3/s条件下,半交换时间为226 h,587 h后达到90%的交换状态,且径流加倍,对应交换时间近似线性递减;子区域水交换差异由潮和径流的相互作用决定,径流越大,靠向上游河段水体交换得越快,径流减小时近河口区段水体交换变快,而中游河段交换变慢。

Model of water exchange in Daliaohe tidal river

Based on the conservative tracer advection and diffusion method,an integrated hydrodynamic-dispersion model(FVCOM) was used to study the water exchange characters in Daliaohe tidal river.The results of the numerical model show that the river discharge affects significantly the water exchange in Daliaohe tidal river;under the runoff condition of 114 m3/s,half life time is 226 h while the exchange rate of tidal river reaches 90% after 587 h,and a double increase in the runoff causes approximate linear decrease of corresponding water exchange time.The water exchange features in the branch regions differ with tidal and runoff interaction,so that with the greater runoff upper reaches exchange faster,in comparison of the fast exchange in the smaller runoff condition near estuary sections and slowly exchange in the middle reaches.