过冷层状云中飞机播云有效区域的模拟研究  

RESEARCH ON SIMULATION OF EFFECTIVE RANGE FOR CLOUD SEEDING BY AIRCRAFT WITHIN SUPER-COOLED STRATUS

作　　者：余兴 王晓玲 戴进 

机构地区：[1]陕西省气象科技创新基地,西安710015 [2]陕西省气象学校,西安710015

出　　处：《气象学报》2002年第2期205-214,共10页Acta Meteorologica Sinica

基　　金：国家科技部"西部开发科技行动"重大攻关项目 (2 0 0 1BA90 1A41);中国气象局吉林省人民政府人工影响天气联合开放实验室基金课题

摘　　要：根据飞机人工增雨作业个例 ,利用层状云中催化剂输送扩散的三维时变模式 ,对过冷层状云中播云产生的有效区域、催化剂水平输送和扩散速率等进行了模拟研究。结果表明 :(1)飞机播云 4 5min线长 32 7km ,投影有效面积和有效体积在播云刚结束时 (5 0分 )达到极大 ,其值分别为 70 7km2 和 2 98.0km3 ,有效扩展宽度和厚度为 2 .5 1km和 0 .4 2km ;(2 )有效作用时段为 2 0～ 80min ,其间的投影有效面积平均值为 5 13.3km2 ,平均有效扩展宽度和厚度分别为 2 .4 1km和 0 .4 5km ;(3)在扩散作用下 ,投影有效面积和有效体积先随时间不断增加 ,达到极值后逐渐减小 ,播云结束 (5 5分 )后 ,云中的有效区域消失 ,其间的投影有效面积平均值为 389.7km2 ,平均有效扩展宽度和厚度分别为 2 .34km和 0 .4 4km ;(4)云中催化剂水平输送 1h的平均值达到 6 5km ,仅与风场有关。催化剂扩散速率 1h平均为 0 .82m/s,与风、温、湍流有关 ;(5 )在飞机增雨作业时 ,飞行方案的设计必须是严格科学的 。It is important to know the range affected by seeding agent in rain enhancement with aircraft. Based on the requirement of effective seeding concentration (10 1/L), the concept of effective range is put forward. And its characteristics such as effective area and volume, expanding depth and width as well as horizontal transport and diffusive rate are obtained by simulating results from a three dimensional model, which deals with transport and diffusion of seeding agent within super cooled stratus. Taking an operational case of rain enhancement as example in the simulation, the results show that: (1) the cloud seeding by airplane takes 45 minutes, the length is 327 km. Five minutes after finish seeding, maximum effective volume and maximum projectively effective area on the ground reach their extremes, 298.0 km 3 and 707 km 2, respectively, its effective expanding depth is 0.42 km , and its width 2.51 km . (2) Effective duration lasts from 20 to 80 minutes. During that time, average projectively effective area is 513.3 km 2, and average effective expanding depth and width are 0.45 km and 2.41 km, respectively. (3) With the effect of turbulence, the effective area and volume increase with the time, and decline after reach their extremes. Effective range disappears 55 minutes after finish seeding. For this while, average projectively effective area is 389.7 km 2, average effective expanding depth and width are 0.44 km and 2.41 km, respectively. (4) Horizontal transport distance is only related to wind. The avenage reached 65 km after 1 hour. And diffusive rate is connected with wind, temperature and turbulence, 1 hour's average is 0.82 m/s. (5) The scheme design of cloud seeding should be scientific to prompt efficiency of rain enhancement.

关 键 词：层状云 扩散速率 飞机增雨 人工增雨作业 风场 水平输送 扩散作用 机播 模拟研究 利用 

分 类 号：P481[天文地球—大气科学及气象学] P426