In this paper, we investigate the aerosol cloud flow physics during three respiratory actions by humans (such as coughing, talking, and breathing). With given variables (i.e., velocity, duration, particle size and number of particles, and ambient conditions), the standoff safe distance during coughing, talking, and breathing should be the distance where virus-laden droplets and aerosols do not have significant transmission to another person. However, at a critical distance, the aerosol cloud flux can still be extremely high, which can immediately raise the transmission in a localized area to another person during a static condition. In this study, computational fluid dynamics analysis of selective respiratory actions has been carried out to investigate the effect of the standoff distance and assess the importance of social distancing in indoor places. The prediction of the aerosol transport due to flow generated from coughing, talking, and breathing was obtained by applying the Eulerian–Lagrangian approach. From the simulation results, it can be concluded that the aerosols released due to continuous talking travel a similar distance to that released due to sudden coughing. On the other hand, aerosols exhaled from breathing do not travel a long distance but float in air for a long time.

中文翻译：

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在人类咳嗽，说话和呼吸过程中模拟气溶胶云的空气动力学

在本文中，我们研究了人类在三种呼吸动作（例如咳嗽，说话和呼吸）过程中的气溶胶云流物理现象。在给定变量（即速度，持续时间，颗粒大小和数量以及环境条件）的情况下，咳嗽，说话和呼吸期间的对峙安全距离应为载有病毒的飞沫和气溶胶不会显着传播至的距离。另一个人。但是，在临界距离处，气溶胶云通量仍可能非常高，这可以在静态条件下立即提高局部区域中向其他人的传播。在这项研究中，对选择性呼吸动作进行了计算流体动力学分析，以研究对峙距离的影响，并评估室内距离社交距离的重要性。通过应用欧拉-拉格朗日方法，可以预测由于咳嗽，说话和呼吸所产生的流量引起的气溶胶传输。从模拟结果可以得出结论，由于连续说话而释放的气溶胶的传播距离与突然咳嗽所释放的气溶胶的传播距离相似。另一方面，从呼吸中呼出的气溶胶不会长距离传播，而是长时间漂浮在空气中。可以得出结论，由于连续讲话而释放的气溶胶的传播距离与突然咳嗽所释放的气溶胶的传播距离相似。另一方面，从呼吸中呼出的气溶胶不会长距离传播，而是长时间漂浮在空气中。可以得出结论，由于连续讲话而释放的气溶胶的传播距离与突然咳嗽所释放的气溶胶的传播距离相似。另一方面，从呼吸中呼出的气溶胶不会长距离传播，而是长时间漂浮在空气中。