区域谱元正压大气模式台风移动数值模拟试验

Numerical Simulation of Typhoon Movement with a Regional Spectral Element Barotropic Atmospheric Model

针对地图投影坐标系下的正压原始方程组,将计算区域按三角形元进行分解,在三角形元内用三角形截断的勒让德多项式的积为插值函数对变量进行谱分解,发展出区域正压谱元大气模式.采用固定边界条件,以2006年5月15日08时500 hPa位势高度和风场为初值,在勒让德多项式最高阶数为3和7这两种情形下开展0601号台风"珍珠"移动的数值模拟试验.结果表明,数值模式模拟的风压场关系合理,数值模式的实现是成功的.

Sharing advantages of spectral method and finite element method,a spectral element method is used in numerical study of geophysical fluid dynamics.By solving barotropic primitive equations with spectral element method,a regional barotropic atmospheric model is developed.In the model,computational domain is broken into a series of triangular elements,and variables in each element are represented as a high order Lagrangian interpolant with products of Legendre polynomials with triangular truncation.With geopotential and wind at 08 o’clock on 15 May 2006 on pressure level of 500 hPa taken as initial value and fixed lateral boundary condition,simulations of typhoon movement with maximum orders of Legendre polynomials 3 and 7 are carried out,respectively.It showns that the simulated relation between wind and pressure is rational and realization of the numerical model is successful.