流体动力学数值计算中两种自由面格式的比较

COMPARISON BETWEEN TWO FREE SURFACE DIFFERENCE SCHEMES IN NUMERICAL SIMULATION OF FLUID DYNAMICS

Ｒｉｃｈｔｍｙｅｒ等指出，流体动力学数值计算中的自由面条件可取为或两种形式，对这两种自由面条件进行了比较和分析。结果表明，前一种自由面条件对凝聚态和气态物质都是适用的，但后者只对凝聚态物质适用，用于气态物质时，误差较大。

R.D. Richtmyer et al pointed out that the free surface condition in the numericalsimulation of fluid dynamics can be taken as the folloing two types:where p is the pressure,q the artificial viscosity,J and n refer to the free surface netpoint and the time t = n△t ,respectively.△t is the time step.In this paper,both thefree surface conditions are compared and analyzed.The research results indicate that the first con-dition is suitable either for condensed matters or gases,but the second is only suitable for con-densed matters. When it is applied for gases,the error of numerical results is large.