Journal of Shanghai Jiao Tong University ›› 2023, Vol. 57 ›› Issue (2): 177-182.doi: 10.16183/j.cnki.jsjtu.2021.337

Special Issue: 《上海交通大学学报》2023年“船舶海洋与建筑工程”专题

• Naval Architecture, Ocean and Civil Engineering • Previous Articles     Next Articles

Modification of Velocity Formulations in a Two-Layer Boussinesq-Type Model for Water Waves

LIU Zhongbo1(), HAN Qingliang1, REN Shuangshuang1, WANG Yan1, FANG Kezhao2   

  1. 1. College of Transportation Engineering, Dalian Maritime University, Dalian 116026, Liaoning, China
    2. State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China
  • Received:2021-09-06 Revised:2021-12-10 Accepted:2021-12-16 Online:2023-02-28 Published:2023-03-01

Abstract:

In order to improve the accuracy of velocity formulation in a Boussinesq-type wave model, with a two-layer Boussinesq-type model with the highest spatial derivative of 2 being chosen as the research object, a third-order term with constant coefficient is proposed to modify the velocity formulation. The coefficient is optimized by minimizing the error between the summation of the integration of horizontal and vertical velocities of the equation and that of the analytical linear Stokes wave velocity components in the range of 0<kh< 8 (where k is wave number, h is still water depth). At a 1% tolerance error, the applicable water depths of the modified formulations for horizontal and vertical velocities are up to kh=7.34 and kh=7.83, respectively, which are larger than those of the original formulations. The evolution of the steady-state wave and the focused wave is numerically simulated by using the numerical model. The horizontal velocity under the maximum surface elevation crest is in good agreements with the analytical solution of stream function and published experimental data, which verifies the effectiveness of the modified formulations. The studies show that the velocity accuracy of the improved equation is greatly improved. This method provides an important reference for the improvement of velocity field of other Boussinesq-type models.

Key words: Boussinesq-type equation, velocity formulation, analytical solution, numerical simulation

CLC Number: