中文摘要：

钱塘江河口潮强流急，涌潮汹涌，是典型的强混合型河口，其盐水入侵程度远强于其它潮汐河口。基于Godunov格式的有限体积法建立了涌潮作用下二维高精度盐水入侵数学模型，结合实测潮汐、涌潮和氯度资料分析，研究了涌潮对钱塘江河口盐水入侵的影响。结果表明，涌潮促使盐水入侵加剧，导致时间上和纵向上氯度变率增大，涌潮是形成盐度锋的动力机制。同时，涌潮紊动激烈，促使氯度垂向分布均匀。另外，还对氯度控制方程中扩散系数的取值进行了讨论，认为钱塘江河口扩散系数取102 m2/s量级较为合适。

英文摘要：

With strong tide, rapid flow and turbulent tidal bore, Qiantang Estuary is a typical well-mixed one. Its saltwater intrusion is far stronger than other tidal estuaries. Based on a finite volume method with Godunov scheme, a 2D saltwater intrusion mathematical model affected by tidal bore was established. Com？bining with the field data analysis for tide,tidal bore and chlorinity,the effect of the tidal bore on saltwa？ter intrusion of Qiantang Estuary was studied. The tidal bore increases the aggravation of saltwater intru？sion,resulting in intensification of the gradient in time domain and in lengthways. The tidal bore is the ki？netic mechanism to form salinity front. Meanwhile,the fierce and turbulent tidal bore makes chlorinity even in vertical distribution. In addition, the value of chloride diffusion coefficient in the chlorinity control equa？tion has been discussed, and it is appropriate to take the diffusion coefficient in Qiantang Estuary for 102 m2/s magnitude.