People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor ventilation. The exhaled particles may be inhaled by the susceptible person, deposited on the surface and suspended in the elevator, which can result in direct and indirect transmission. However, whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains unknown. In this study, the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics (CFD) simulations. The flow field was simulated with the RNG k-ξ turbulence model and the Lagrangian method was adopted to track particle trajectories. The effects of air vent layout and airflow rate on particle transmission were analyzed. We found that more than 50% of exhaled particles (average value) were suspended in the cabin and difficult to discharge under the investigated ventilation strategies. The deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation, which led to a high risk of contact infection. Increasing the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator. A more proper ventilation strategy should be explored for the elevator to control transmission risk.

由于电梯轿厢拥挤、通风不良，乘坐电梯的人存在呼吸道感染的风险。呼出的颗粒物可能被易感者吸入，沉积在物体表面并悬浮在电梯内，从而导致直接和间接传播。然而，电梯采用的通风口设计能否有效降低呼吸颗粒物的传播风险仍是未知数。在本研究中，通过经过验证的计算流体动力学 (CFD) 模拟研究了商用电梯中使用的四种常见通风策略下的颗粒分散情况。采用RNG k-Σ湍流模型模拟流场，采用拉格朗日法跟踪粒子轨迹。分析了通风口布局和气流速度对颗粒传输的影响。我们发现，在所研究的通风策略下，超过 50% 的呼出颗粒物（平均值）悬浮在舱内且难以排出。渗透通风时，易感者身上颗粒物沉积率高达39.14%，接触感染风险较高。由于电梯内气流分布较差，增加通风量并不能显着降低颗粒物吸入比例。电梯应探索更合理的通风策略，控制传播风险。