钱塘江口涌潮的二维数值模拟

Two-Dimensional Numerical Modelling of Bores in the Qiantang Estuary

摘要: 应用二维有限体积法、Osher格式及间断拟合法,计算了钱塘江河口涌潮产生、发展到消亡的全过程。该算法能保证水量和动量守恒,且能适应水深巨大变化和动边界。根据钱塘江涌潮的特点,可将其合理概化为一线潮。在网格尺寸较大情况下,计算的一线潮仍保持高分辨率,能准确满足水力学间断条件,且计算量小,可以在微机上实现。在对某实测半日小潮进行率定后,对随后的大潮进行了验证计算,涌潮的主要特征(如涌潮高度、移速、水位和流场等)与实测资料符合良好,证实了模型的合理性和模拟能力。

Abstract: Histories of Gores in the Qiantang Estuary,are modelled by using a two-dimensional finite-volume,Osher scheme,and a discontinuity-fitting method. The algorithm ensures mass and momentum conservation,and can be applied to cases with irregular morphography,and moving boundaries. Based on a simplification a line-bore,the modelling can be done on a coarse mesh by a microcomputer,After having calibrated against a typical semi-diurnal tide,the model is used to predict the succeeding semi-diurnal tide for validating its reasonability and applicability.