水平网格计算频散性的研究

IMPACT OF HORIZONTAL GRID ON INERTIAL-GRAVITY WAVE

摘要: 从线性浅水方程组出发, 在Arakawa A—E网格、Z网格和Eliassen网格上, 分可分辨和不可分辨两种情况, 从频率和群速方面讨论了这7种网格的计算频散性, 并指出了每种网格出现错误群速的水平尺度范围。结果表明:在可分辨的情况下, Z、C和Eliassen网格较其它网格效果好; 在不可分辨的情况下, B网格较其它网格效果好。
- 网格;
- 惯性重力波;
- 频散方程;
- 群速
Abstract: The computational dispersion properties of Arakawa A-E, Z and Eliassen grids, based on the linear swallow-water equations, are analyzed in terms of frequency and group velocity characteristics respectively for irresoluble and resoluble models. The horizontal scale ranges in which wrong group velocities will result in for every grid are pointed out. It is shown that for the resoluble model, Z, C and Eliassen grids are the best in dispersion characteristics among all grids considered and for the irresoluble model, B grids are the best.
- Grid;
- Inertial-gravity wave;
- Disperse equation;
- Group velocity

图 1 各种网格的变量配置图

(, d为格距)

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图 2a 的7种网格和解析解的频散图

(x方向的坐标为, y方向的坐标为, z方向的坐标为, 取值范围为[0, 1])

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图 2b 的7种网格和解析解的频散图

(坐标与图 2a的相同, 但取值范围为[1, 2])

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