A coupled numerical model is developed based on the spectral element method (SEM) and boundary element method (BEM) to predict the characteristics of tsunami wave response on Pohang New Harbor (PNH), South Korea, and Paradip Port, India. The current numerical model is developed to analyze the impacts on the coastal region with slowly varying bathymetry under the resonance conditions. In this method, the boundary integral equation of each boundary segment is discretized into the spectral elements using the Chebyshev’s polynomial, and the corresponding boundary integrals are transformed using the Jacobian of transformation. This leads to a highly accurate depiction of the boundary edges or corners of the complex domain. Convergence and error analyses are conducted on the rectangular port using the BEM and the present method, which shows that the later approach enhances the overall numerical accuracy of the model. The simulation results for normal day wave (ordinary wave propagating in the ocean under normal conditions) and tsunami waves are validated with previous studies and measurement data at Pohang New Harbor (PNH), South Korea. In addition, the calculated spectral density for tsunami waves at PNH is also compared with the Hokkaido tsunami (reported on July 12, 1993) data at tide gauge record station in Pohang. The amplification factor is determined for normal day wave and tsunami waves at key locations inside the PNH and Paradip Port for different directional incident waves. Further, the spectral density is also estimated at the same locations with respect to the wave period to understand the consequences of tsunami waves on the coastal ports. Therefore, the coupled numerical model is an efficient tool to predict tsunami wave impact on a realistic port. The causes and countermeasure are suggested to reduce the risk of normal day waves and tsunami waves.

基于光谱元素方法（SEM）和边界元素方法（BEM），建立了一个耦合数值模型，以预测韩国浦项新港（PNH）和印度Paradip港口的海啸响应特征。开发了当前的数值模型，以分析在共振条件下缓慢变化的测深仪对沿海地区的影响。在这种方法中，使用切比雪夫多项式将每个边界段的边界积分方程离散化为频谱元素，并使用雅可比变换对相应的边界积分进行变换。这导致对复数域的边界边或角的高精度描述。使用BEM和本方法在矩形端口上进行收敛和误差分析，这表明后面的方法提高了模型的整体数值精度。正常日波（普通波在正常条件下在海洋中传播）和海啸波的模拟结果已通过韩国浦项新港（PNH）的先前研究和测量数据得到验证。此外，还将计算的PNH海啸波谱密度与浦项潮汐记录站的北海道海啸（1993年7月12日报道）数据进行了比较。对于不同方向的入射波，在PNH和Paradip端口内关键位置的正常日波和海啸波的放大系数是确定的。此外，还估计了相对于波浪周期的相同位置处的光谱密度，以了解海啸对沿海港口的影响。因此，耦合数值模型是预测海啸对实际港口影响的有效工具。建议减少产生正常日波和海啸风险的原因和对策。