三维可压缩大气中的云尺度模式

我们设计了一个三维云尺度模式,它的控制方程由二部分组成:一是Euler式的可压缩运动方程,连续方程,压力变化方程及热力学方程;二是Lagrange式的云-降水微物理方程组。由于声波的存在对各个方程积分过程的影响程度不同,运用了时间分离方法。网格结构设计了二种:一般的和交叉的,并分别采用了松野积分方案和半隐式积分方案。模式经过严格的调试以后,进行了多个个例模拟研究,表明模式是稳定的,给出了合理的三维对流的发展图象,不仅模拟出垂直对流环流,而且模拟出对应的水平涡坏。利用该模式,研究了水平涡坏的形成和发展对云内下沉气流激发的影响和作用。

A three-dimensional cloud-scale model suitable for compressible atmosphere

A three-dimensional cloud-scale model has been designed. The governing equa-lions of model are composed of compressible motion equations, continuity equa-lion, pressure equation, thermodynamics equation, those are of Euler type, and cloud-precipitation microphysics equations, those are of Lagrange type. In the solving governing equations the splitting procedure has used, the both mesh of general and staggering have been structured, the integration schemes have adopted the Eulerian backward difference method for the general mesh and semiimplicit method for staggering mesh. Several experiments of modelling have fin-fished and the results have shown a reasonable three-dimension image for deep convection. Using this model the effects of horizontal vortex circulation follow-ing the vertical one on the formation and developing of downdraft airflow within cloudy domain have been studied.