抛物型缓坡方程的变分及数值模拟

The variational principal and numerical simulation of parabolic mild-slope equation

1.
College of Traffic, South China Unversity of Technolegy, Guangzhou 510641;State Key Laboratory of Coastal & Offshore Engineering Dalian) University of Technology, Dalian 116023
2.
College of Traffic, South China Unversity of Technolegy, Guangzhou 510641

摘要: 对线性水波的折射一绕射问题应用变分原理,对非等深、具有缓坡和不连续的底被导出了一种修改的抛物型缓坡方程近似模型,可预测三维地形上波浪的折射一绕射。同抛物型缓坡方程的线性方程进行了对比。通过数值模拟方法进行数值求解,表明本方法可用于地形条件下的波浪折射一绕射问题。
- 变分原理 /
- 水波 /
- 折射 /
- 绕射 /
- 修改抛物型缓坡方程 /
- 数值模拟
Abstract: The modified version of the perabolic mild-slope equation is derived by the variational principle.The modified parabolic mild-slope equation is shown to be capable of describing for wave propagation over a bed consisting of substantial variations in water depth and to predict wave refraetion-diffraetiort with three-dimension topography.The modified parabolic mild-slope equation has been compared with parabolic mild-slope equation.Numerical examples demonstrate the practical applicability of the modified parabolic mild-slope equation.
- Variational principle /
- midified parabolic mild-slope equation /
- refraction-diffraction /
- numerical simulation /

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