有限空间内飞沫颗粒传播规律的数值研究  

Numerical study on the spread and diffusion law of droplet particles in limited space

作　　者：罗婷[1] 胡卓焕[1] 杨茉[1] LUO Ting;HU Zhuohuan;YANG Mo(Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学上海市动力工程多相流动与传热重点实验室,上海200093

出　　处：《流体机械》2021年第7期83-90,共8页Fluid Machinery

基　　金：国家自然科学基金重点项目(51736007)。

摘　　要：采用Realizable k-ε湍流模型并运用多组分欧拉-拉格朗日方法离散相模型,模拟了有限空间内说话、咳嗽和打喷嚏3种生理活动中产生的可吸入飞沫颗粒的输送过程,分析了不同生理活动时可吸入飞沫颗粒在有限空间内的分布特点,研究了其传播扩散规律以及影响因素。结果表明:在3种生理活动下产生的飞沫初期都以“飞沫羽流”的形态进入到空气中传播并扩散,而后逐渐转化为“飞沫旋流”继续沿喷射方向传播,且“旋流”的形成对飞沫在喷射垂直方向上扩散扰动具有明显的削弱作用,此时飞沫在空气中所占的质量分数最大。此外,打喷嚏时在喷射方向上的传播速率为说话的2.5倍,而喷射垂直方向的扩散速率为说话的2倍,且其影响波及范围最广。有限空间内的强迫对流不仅会对传播过程中飞沫的形态产生影响,且同时强化飞沫的蒸发作用。本文研究成果可为飞沫传播传染病的防治工作提供参考。The Realizable k-εturbulence model and a multi-component Eulerian-Lagrangian approach of discrete phase model were applied to simulate the transport process of inhalable droplets in air for three different physiological activities of speech,coughing and sneezing.The distribution characteristics of inhalable droplet particles in different physiological activities in limited space were analyzed,and its spread and diffusion law and influencing factors were studied.The results show that the initial droplets produced in three different physiological activities all enter into the air and spread in the air in the form of“droplets plume”,and then are gradually transformed into“droplets swirl”to continue to spread in the direction of injection.The formation of“droplets swirl”is a significant weakening effect on the diffusion disturbance of droplets in vertical direction.At this time,the droplets account for the largest mass fraction in the air.In addition,during the sneezing,spread speed in the direction of injection is 2.5 times of that during talking,whereas the diffusion rate in the vertical direction is twice that during talking and its impact is the widest.Furthermore,forced convection in limited space not only affects the form of droplets during propagation,but also strengthens the evaporation effect of droplets.The research results can provide reference for the prevention and treatment of the infectious diseases transmitted by droplets.

关 键 词：有限空间 飞沫颗粒 传播扩散 数值模拟 传染病 

分 类 号：TH137.8[机械工程—机械制造及自动化] TU834.4[建筑科学—供热、供燃气、通风及空调工程]