To explore the influence of turbulent motion on collection efficiency, the collecting processes of different diameter aerosols captured by four diameter raindrops were estimated by employing numerical simulation with different turbulent intensities, respectively. Considering the characteristics of scavenging process in the turbulent flow field, the concept of collision probability was introduced to give the new definition of computational formula of collection efficiency in turbulent flow condition. On the basis of the concept, the influence of turbulent effect on the collection efficiency was discussed and analyzed. The numerical results show that the collision probability distributions for particle of different diameters are affected by background turbulent intensity. Furthermore, collection efficiency is strongly affected by turbulent intensity for dp≤5 μm. The influence of turbulent effect on collection efficiency depends on the density and diameter of particle, which was independent of the raindrop diameter.
华凤皎, 亢燕铭, 钟珂. 湍流效应对雨滴表面粒子捕集过程的影响[J]. 中国环境科学, 2017, 37(1): 13-20.
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