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首先建立了一个模拟层状云中催化剂扩散的三维时变烟团轨迹模式。该模式能够模拟层状云中多条（与风向）非垂直撒播线源的催化剂扩散特征。在模式中，详细考虑了地形、垂直风切变对催化剂扩散的影响以及催化剂播散参数的时空变化和催化剂的湿清除效应以更接近于实际过程。其次建立了一个细网格三维非静力中－β尺度动力学预报模式，用于模拟大气流场和湍流场，以其作为烟团轨迹模式的背景场。最后根据１９９６年３月３１日０８时实测常规气象资料和１４时飞机实际播撒参数，对陕西省关中地区飞机人工增雨作业中的催化剂扩散进行了数值模拟，对不同的大气层结和扩散参数做了敏感性试验分析。模拟结果表明：（１）在非均匀、非定常及非垂直直线源情况下，层状云中催化剂扩散的浓度等值线空间分布较复杂，不满足高斯分布。（２）催化剂的扩散与湍流扩散系数、风场分布相对应，水平扩散范围大于垂直扩散范围。（３）不稳定层结有利于催化剂扩散和多条线源的合并，扩散系数越大，扩散范围越大，线源间合并越早，撒播的线源间距可以大些。（４）陡峭地形对低层风场和湍流场影响较大。
First, a model of three-dimensional time-varying fume trajectory that simulates the diffusion of catalysts in layered clouds was established. This model is able to simulate the catalyst diffusion characteristics of multiple (non-perpendicular) sowing line sources in layered clouds. In the model, the effects of topography and vertical wind shear on the diffusion of catalyst are discussed in detail. The temporal and spatial variations of the catalyst diffusion parameters and the wet scavenging effect of the catalyst are taken into consideration in order to get closer to the actual process. Secondly, a three-dimensional mesoscopic non-static mid-β-scale dynamic prediction model is established to simulate the atmospheric flow field and the turbulent flow field as the background field of the smoke track pattern. Finally, according to the measured conventional meteorological data at 0800hrs on March 31, 1996 and the actual sowing parameters at 14hrs, the diffusion of catalyst in the artificial weathering of aircraft in the Guanzhong area of Shaanxi Province was numerically simulated, and different atmospheric junction and diffusion parameters Sensitivity test analysis. The simulation results show that: (1) In the case of non-uniform, unsteady and non-vertical linear sources, the spatial distribution of concentration contours of catalyst diffusion in layered clouds is complex and does not satisfy the Gaussian distribution. (2) The diffusion of catalyst corresponds to turbulent diffusion coefficient and wind field distribution, and the horizontal diffusion range is larger than the vertical diffusion range. (3) Unstable stratification is favorable for the catalyst diffusion and the merging of multiple line sources. The larger the diffusion coefficient, the larger the diffusion range, and the earlier the merger between the source and the source, the spacing of the source of the broadcast can be larger. (4) The steep terrain has a great influence on low-level wind field and turbulent field.