摘要
本文研究了用压缩空气爆破(薄膜爆破,激波管等)和火药爆炸非催化方法触发冰晶产生的作用机制。我们通过大量实验认为超声波和冲击波的作用不一定能够触发过冷水滴冻结,而超声速气流的绝热膨胀冷却作用则是触发冰晶产生的确切机制。然后设计了超声速气流发生装置并在过冷雾中进行触发冰晶产生的实验。结果表明,超声速气流(M=1.1)触发冰晶产生非常有效。阈温为-2℃。冰晶产生的临界压强为2.1atm,阈压随实验温度升高而增加,当总压超过阈压0.2—0.3atm时,冰晶大量产生。这些结果与超声速绝热膨胀理论相一致。
The mechanisms on ice crystals generation triggered by non-catalysis method, including blast by the compressed air (burst of the film and shock tube) and detonation of powder, are investigated. The shock wave-high pressure mechanism and the supersonic cavitation mechanism are preliminarily negated at first based on qualitative experimental while the supersonic adiabatic expansion is considered to be the true mechanism leading to ice crystals generation. Then, a supersonic air flow generator for triggering ice crystals generation in supercooled fog is designed. The experimental results show that a supersonic air flow (M = 1.1) has a great effect on produce of the ice crystals. The threshold temperature is -2℃. The critical pressure is 2.1 atm. The threshold pressure increase as the experimental temperature increase. A large number of ice crystals are produced when the total pressure is 0.2-0.3 atm higher than the threshold pressure. The results are consistent with the theory on supersonic expansion.
出处
《气象学报》
CSCD
北大核心
1991年第2期198-204,共7页
Acta Meteorologica Sinica
基金
国家自然科学基金
