Multiphase Modelling and Experimental Characterization of Respiratory Microdroplet Suspension and Resuspension Dynamics Near Surfaces

近表面呼吸微滴悬浮和再悬浮动力学的多相建模和实验表征

基本信息

批准号：
2039310
负责人：
Anand Jagota
金额：
$ 38.11万
依托单位：
Lehigh University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-01 至 2023-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2039310&HistoricalAwards=false
关键词：
Multiphase Modelling Experimental Characterization Respiratory

项目摘要

The main transmission routes for COVID-19 are respiratory droplets and close contact. Understanding environmental spreading pathways of COVID-19 is critical for improving safety practices. Although the flow physics of respiratory droplets at large length scales has been the focus of many studies, the microscale dynamics of the suspension behavior of individual respiratory droplets on common personal protective equipment (PPE) surfaces and the secondary exposure risk due to resuspension of those droplets have not been systematically evaluated. Initial studies show that environmental conditions such as humidity and temperature as well as surface properties, e.g. surface chemistry, roughness and wettability have significant effects on the evolution mechanism of aerosols and droplets. In particular, there is no comprehensive study on how temperature and humidity influence the aerodynamics and surface interaction of aerosols. The goal of this project is to provide fundamental understanding of the interaction between individual respiratory microdroplets and PPE surfaces under external disturbance such as body motion, through combined computational modeling and experiments. This research will help explore potential approaches that can be practiced by medical staff and general public to control motion, humidity, temperature, and surface modification that reduces aerosol-based virus spreading. The project will also incorporate research into education of undergraduate and graduate students in class, making a droplet-surface simulation tool to be made available to the research community, and outreach to K-12 and minority students.The goal of this project is to provide both a fundamental understanding of thermal-humidity-temporal microdroplet dynamics and a prediction tool for microdroplet surface interaction. The specific aims of the proposal work are to: (i) Develop a 3D multi-phase computational model for evaporation, transport, suspension, adhesion, and resuspension dynamics of respiratory droplet on various surfaces; (ii) Generate individual mimetic-virus laden respiratory microdroplets, with chemical composition and sizes similar to respiratory droplets, and investigate systematically the dynamics of the suspension and resuspension behavior of these droplets near various surfaces in a controlled environment; and (iii) Explore the effects of temperature, humidity, surface properties, and external disturbance on the suspension and resuspension behavior of droplets and suggest potential approaches for minimizing the aerosol spreading of virus. The integrated computational and experimental approach will create comprehensive understanding of the droplet-based virus transport and evolution as a function of humidity, temperature and surface characteristics.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

COVID-19的主要传输路线是呼吸液滴和密切接触。了解Covid-19的环境扩散途径对于改善安全实践至关重要。尽管大尺度上的呼吸液滴的流动物理学一直是许多研究的重点，但在共同个人保护设备（PPE）表面上单个呼吸液滴的悬架行为的显微镜动力学以及由于这些液滴的重悬于这些液滴的重悬而导致的二次暴露风险。初步研究表明，湿度和温度以及表面特性等环境条件，例如表面化学，粗糙度和润湿性对气溶胶和液滴的演化机制具有重大影响。特别是，没有关于温度和湿度如何影响气溶胶的空气动力学和表面相互作用的全面研究。该项目的目的是通过组合计算建模和实验在外部干扰（例如身体运动）下对单个呼吸微单位和PPE表面之间的相互作用提供基本理解。这项研究将有助于探索医务人员和公众可以实践的潜在方法，以控制运动，湿度，温度和表面修饰，从而减少基于气雾剂的病毒扩散。该项目还将纳入课堂上的本科和研究生的教育研究，使研究社区提供液滴表面仿真工具，并向K-12和少数族裔学生提供宣传。该项目的目的是为热 - 湿度 - 周期性微观型微粒动力学和预测工具提供基本的了解，以使其对微观互动进行预测工具。提案工作的具体目的是：（i）开发一个3D多相计算模型，用于蒸发，运输，悬架，粘附和重悬于呼吸液滴的动力学；（ii）产生单个模拟性病毒呼吸微粒，具有化学成分和大小类似于呼吸液滴，并系统地研究了这些液滴在受控环境中各个表面附近这些液滴的悬架和重悬行为的动力学；（iii）探讨温度，湿度，表面特性以及外部干扰对液滴的悬浮悬浮和重悬行为的影响，并提出了最大程度地减少病毒气溶胶扩散的潜在方法。集成的计算和实验方法将对基于液滴的病毒运输和进化的全面理解，这是湿度，温度和表面特征的函数。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点和更广泛影响的审查标准通过评估来获得支持的。