MASS CONSERVATION BEHAVIOR OF WAVE EQUATION MODEL FOR SOLVING SHALLOW WATER EQUATION

摘要

Wave equation model (WEM) first developed by Lynch and Gray is one of accurate and effective numerical methods to resolve shallow water equations. This paper shows the numerical consistency of the second- order wave equation and the first- order continuity equation, analyzes the error between them. This paper also shows that the numerical friction factor τ_0 appearing in wave equation is of key importance to the numerical solutions and mass conservation of wave equation model. Numerical calculations of M_2 tidal waves in rectangular harbor and a quarter annular harbor are made to demonstrate that it is possible to find a proper numerical friction factor τ_0 with which accurate solutions and satisfactory mass conservation can be achieved by wave equation model.