随机波浪作用下黑泥湾冲淤演变的数值模拟

近岸海域潮流、波浪动力条件复杂,单纯考虑潮流输沙对底床冲淤演变的影响可能存在较大的偏差。基于局地较长时期海浪场统计特征,将随机波浪因子引入底床冲淤演化模拟研究中,采用ECOMSED模式进行了不同波浪动力条件影响下黑泥湾海域冲淤演化的数值模拟,并与现场观测资料进行了比较,取得了较好的结果。结果表明,黑泥湾及附近海域存在较稳定的N—S向潮余流,这在整体上是本区泥沙输运的重要影响因素;湾内海域基本处于冲淤动态平衡,冲淤格局与其地形、海流流速和波浪场分布有关,楮岛周围与镆铘岛东面近岸海域以侵蚀为主,镆铘岛南部近岸以淤积为主;随机波浪要素的引入对冲淤演变模拟结果有较大的影响,引入波浪要素后的模拟的结果与海图更为接近。

NUMERICAL SIMULATION OF RANDOM WAVE-INDUCED EROSION AND DEPOSITION PATTERN IN THE HEINI BAY

The wave and current systems in nearshore waters are quite complicated. Deviation may occur in simulation of seabed evolution if only the current factor is taken into account. In this paper, according to the local statistical characteristics of wave field, we introduced the random wave factor into the simulation of seabed erosion and accretion pattern in the Heini Bay based on ECOMSED model. The simulated result of tidal current field agrees well with the in-situ observation data. The results show that there is a stable N-S tidal residual current in the Heini Bay and adjacent areas, which is a key factor to sediment transportation. The seabed is relatively stable except for erosion outside of the Chu and Moye islands and accretion in southern Moye island. The simulation result is more close to the observation compared with the sea chart.