雨团模型中扰动的波谱分析及其位势稳定度

为研究雨团模型中扰动的波谱分析及其位势稳定度,研究了其中由垂直结构方程和边界条件所构成的特征值问题,讨论了湿层结参数的垂直分布与位势稳定度的关系,得到了位势不稳定判据,给出了不稳定模态增长率和稳定模态振荡频率的上、下界,以及模态垂直结构的分布规律。在垂直方向,当湿层结参数均大于0时,所有模态都是稳定的; 而当其在某处小于0时,则满足不稳定判据的模态可有位势不稳定。结果与实际情形大体相一致。

Spectral analysis on perturbation and stability in rain clusters model

Spectral analysis of the perturbing modes in rain clusters model was conducted, and the eigenvalue problem caused by the vertical structural equations and boundary condition in the model was researched. The potential instable criterion was obtained, and the variation ranges of the instable growth rates(or stable oscillation frequency)were presented,together with the distributions of vertical perturbing structure by the relations between vertical distribution of different humid stratification coefficients and potential stability. All the vertical perturbing modes were stable as the humid stratification coefficient was greater than zero. When the coefficient was less than zero, potential instable modes might occur. The main conclusions accord with the fact in general.