Aerial mucosalivary droplet dispersal distributions with implications for disease mitigation
Aerial mucosalivary droplet dispersal distributions with implications for disease mitigation
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DOI：
10.1103/physrevresearch.2.043391
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发表时间：
2020-12-18
影响因子：
4.2
通讯作者：
Kudrolli, Arshad
中科院分区：
文献类型：
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作者：
Chang, Brian;Sharma, Ram Sudhir;Kudrolli, Arshad
我们通过静止空气条件下的物理实验研究了与人类呼气相对应的粘膜唾液在水平表面上的扩散和沉积。通过高速成像观察到合成荧光标记喷雾的尺寸和速度分布与人类喷嚏相当。我们表明，虽然一些较大的液滴遵循抛物线轨迹，但较小的液滴会在空中停留几秒钟，并以与浮力云动力学模型一致的速度缓慢沉降。随着源高度 H 的增加，观察到净沉积分布相应地变得更宽，范围从坐在桌子旁到直立。我们发现沉积的粘膜在源前呈指数衰减，当 H = 0.5 m 时，在距离 x = 0.71 m 处达到峰值，当 H = 1.5 m 时，在距离 x = 0.56 m 处达到峰值，标准偏差接近 0.5 m。超过 99% 的粘膜唾液沉积在 x = 2 m 内，距离源越远，着陆时间越快。然后我们证明，与未遮盖时记录的峰值相比，标准口鼻罩可将粘膜分散的粘膜减少至少一百倍。
We investigate mucosalivary dispersal and deposition on horizontal surfaces corresponding to human exhalations with physical experiments under still-air conditions. Synthetic fluorescence tagged sprays with size and speed distributions comparable to human sneezes are observed with high-speed imaging. We show that while some larger droplets follow parabolic trajectories, smaller droplets stay aloft for several seconds and settle slowly with speeds consistent with a buoyant cloud dynamics model. The net deposition distribution is observed to become correspondingly broader as the source height H is increased, ranging from sitting at a table to standing upright. We find that the deposited mucosaliva decays exponentially in front of the source, after peaking at distance x = 0.71 m when H = 0.5 m, and x = 0.56 m when H = 1.5 m, with standard deviations approximate to 0.5 m. Greater than 99% of the mucosaliva is deposited within x = 2 m, with faster landing times further from the source. We then demonstrate that a standard nose and mouth mask reduces the mucosaliva dispersed by a factor of at least a hundred compared to the peaks recorded when unmasked.