磨刀门水道枯季水动力特性分析

根据2009年12月1025日磨刀门水道上至竹银下至口门近半月的同步实测水文资料,对该水道在大、中、小潮下表、中、底层的水动力特性进行了分析和探讨。结果显示,枯季磨刀门水道总体涨、落潮流速都不大,即使大潮时该水道总体表层涨落潮平均流速分别仅为0.5m/s和0.76m/s;水动力特性一般呈现:表层落潮流速显著大于涨潮流速,底层涨、落潮流速相差不大的规律;表底层涨落潮流速一般呈现随潮型增大而增大的趋势;表层涨潮历时小于落潮历时,底层涨潮历时大于落潮历时;实测结果显示,包括口门及上游河道范围内的表、底层流速出现相反的现象,时段一般出现在经过第一个长时间的落潮流之后的第二个较短落潮时间段内,且沿水深方向的转流点更为靠近表层。

Analysis of Water Dynamic Characteristics of Modaomen Waterway during Dry Season

Analysis and investigation on water dynamic characteristics at the water surface to bottom under spring, middle and neap tides were made based on synchronously observed data for nearly 40km distance from Zhuying upstream to estuary during Dec.10-25, 2009. The results show that the velocities in Modaomen waterway are not speed with only average 0.5m/s and 0.76m/s on water surface respectively during rising and ebb duration in spring. Water dynamic characteristics commonly appear that the velocities during ebbing time are more than that during rising on water surface but there is little difference on bottom. Rising and ebbing velocities increase from neap to spring tides. Tidal rising duration is less than ebb on water surface in the waterway with converse feature on bottom. There is converse flowing phenomena along water depth between water surface and bottom in the Modaomen estuary and waterway during the second ebb duration after the first long time ebbing with revolving location closer to water surface.