灌河口潮汐潮流不对称研究

A Study on Tidal Asymmetry in the Guanhe Estuary

关键词:  灌河口  潮汐不对称  倍潮波

Key words:  Guanhe estuary  tidal asymmetry  overtide

摘要:

基于灌河口2007年5月的潮位、潮流实测数据,对灌河口的潮汐和潮流不对称现象进行研究。首先对潮流、潮位实测数据进行调和分析,探讨灌河口M2分潮及其倍潮波的沿程分布特征,再通过潮位-流速关系图研究M4、M6及M8分潮对潮汐变形的影响,最后利用理论判断法则对灌河口潮汐不对称进行判别。结果表明,灌河口的潮波兼具驻波和行进波的特征,灌河口潮汐不对称主要受M4分潮的影响,呈涨潮主导型。河口口门内最大涨(落)潮流速出现在最低(高)潮位与中潮位之间时刻。M4分潮导致最大涨(落)潮流速增大(减小),最大涨(落)潮流速与最低(高)潮位之间的相位差增大。M6与M8分潮的作用不大。

Abstract:

Tidal asymmetry in the Guanhe estuary was studied basing on the measured tidal elevation and tidal current in May 2007.Firstly, the distributions of M2 and its overtides M4, M6 and M8 were discussed.Secondly, the stage-velocity diagrams were used to study the effects of M2, M4, M6 and M8 on tidal distortion.Finally, tidal asymmetry in the Guanhe estuary was examined using a theoretical method.The results show that tidal motion in the Guanhe estuary has the characteristic of stand wave and progressive wave.Also, tidal asymmetry is flood-dominant and mainly affected by M4.Inside the main channel, maximum flood current and maximum ebb current appear near the mid-tidal elevation time.M4 increases (decreases) the maximum flood (ebb) current, and M6 and M8 play an insignificant role.