Bhattacharya Arup, Ghahramani Ali, Mousavi Ehsan
Department of Construction Science and Management, Clemson University, USA.
Department of Building, School of Design Environment, National University of Singapore, Singapore.
J Build Eng. 2021 Dec;44:102900. doi: 10.1016/j.jobe.2021.102900. Epub 2021 Jun 19.
The effect of the built environment on the predominant indoor airflow patterns is significant. To protect the healthcare workers at the front line from the outbreak of COVID - 19, it is necessary to understand the transmission dynamics of the virus, which has been shown to depend on indoor airflow patterns. In hospital operating rooms (ORs), design requirements pose a unique challenge as the positive pressure in the OR can facilitate virus spread into adjacent spaces, shall a COVID-positive patient require a surgical procedure. Moreover, the turbulent vortexes from door motions could independently increase the probability of virus escape from the OR to the adjacent corridors. Therefore, to obtain critical knowledge about the alteration of flow fields due to door movement in a positively pressurized room and quantify the air mixing across the door, a series of experiments were conducted in a controlled chamber. The results demonstrate significant impacts of the door opening on the airflow patterns. Increased alterations near the door and vortexes penetrating far into the chamber with multiple doors openings warrant further study of the indoor airflow dynamic under door motion. This experimental study proposes an algorithm to quantify the air exchange due to a standard door opening and quantifies this exfiltration of contaminated air up to 2 air changes per hour, that is 10 of the chamber supply airflow rate. The algorithm to quantify the dissipated air quantity and the analyses of interaction between initial conditions and door openings contribute to the originality of this paper.
建筑环境对室内主要气流模式的影响显著。为保护一线医护人员免受新冠疫情的侵袭，有必要了解病毒的传播动态，而这已被证明取决于室内气流模式。在医院手术室中，设计要求带来了独特的挑战，因为如果新冠阳性患者需要进行手术，手术室的正压会促使病毒扩散到相邻空间。此外，门的运动产生的湍流涡旋可能会独立增加病毒从手术室逸出到相邻走廊的概率。因此，为了获取关于正压房间内门移动引起的流场变化的关键知识，并量化门两侧的空气混合情况，在一个受控实验室内进行了一系列实验。结果表明门打开对气流模式有显著影响。门附近变化加剧以及多个门打开时涡旋深入腔室，这使得有必要进一步研究门运动下的室内气流动力学。这项实验研究提出了一种算法来量化标准门打开引起的空气交换，并量化受污染空气的外渗量，每小时可达2次换气，即腔室送风流量的10%。量化耗散空气量的算法以及初始条件与门打开之间相互作用的分析是本文的创新之处。
