RAPID: Energy-Efficient Disinfection of Viral Bioaerosols in Public Spaces: Vital for Lifting of the “Stay-at-Home” Orders during the Covid-19 Outbreak

该项目将提供一个分析框架，以评估新冠肺炎病毒生物气雾剂在公共场所，包括校车、教室和零售店中的感染风险的潜在降低。病毒生物气雾剂可能会导致居住者感染，无论他们是否同时呆在室内，无论是在靠近感染者的地方还是远离感染者的地方。如果上层房间杀菌紫外线(UR-GUV)灯与空气中和表面上的生物气溶胶有效地相互作用，那么它可以提供一种能量占用相对较小的实时空气消毒液。该项目将开发和传播一个开放源码的数值分析框架，包括对UR-GUV消毒的评估，并在网上公开，以提供有助于帮助控制空气传播的公共场所新冠肺炎感染的免费资源。一个有效、实时和可持续的室内空气消毒工程解决方案是帮助防止新冠肺炎传播的重要预防措施，特别是在努力重振国家经济的背景下。该项目将开发基于计算流体动力学(CFD)的数值方法，以再现病毒生物气溶胶通过室内气流传播、通过排气去除、由UR-GUV灭活、由居住者吸入并沉积到不同空间尺度、通风系统以及人口规模和密度的公共场所表面的过程。该项目还将优化吊扇的应用，以提高UR-GUV的消毒效果。这项调查将为病毒气雾剂引起的感染风险和被病毒生物气雾剂污染的表面的UR-GUV感染控制提供新的见解。此外，该项目将考虑两种UV-C光源，一种是传统汞蒸气UV-C灯(UV-C-MV)，另一种是UV-C-LED，以提高能效。这两个UV-C源在消毒、能源效率和运行成本方面的比较为可持续的UR-GUV解决方案提供了希望，以最大限度地减少公共场所的感染风险。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project will provide an analytical framework to assess potential reduction of infection risks from COVID-19 viral bioaerosols in public spaces, including school buses, classrooms, and retail stores. Viral bioaerosols may cause infection for occupants staying both near and far away from infected people, whether staying indoors at the same time or not. Upper-room germicidal ultraviolet (UR-GUV) light can provide a real-time air disinfection solution with a relatively small energy footprint if its light effectively interacts with the bioaerosol both in the air and on surfaces. This project will develop and disseminate an open-source numerical analytical framework including assessment of UR-GUV disinfection and make it publicly available online to provide a free resource useful for helping to control the spread of airborne COVID-19 infections in public spaces. An effective, real-time, and sustainable engineering solution for air indoor space disinfection is an important precaution to help prevent the spread of COVID-19, particularly in the context of efforts to restart the nation's economy. The project will develop numerical methods based on Computational Fluid Dynamics (CFD) to reproduce the processes for viral bioaerosols spread by indoor airflow, removed by exhaust, inactivated by UR-GUV, inhaled by the occupants, and deposited onto surfaces in public spaces of varied spatial scales, ventilation systems, as well as population size and density. This project will also optimize the application of ceiling fans to improve UR-GUV disinfection efficacy. The investigation will provide new insight on infection risk due to viral aerosols and infection control by UR-GUV for surfaces contaminated by viral bioaerosols. In addition, the project will consider two UV-C sources, one by traditional mercury vapor UV-C lamps (UV-C-MV) and another by UV-C-LED for their energy efficiency. The comparison of the two UV-C sources in terms of disinfection, energy efficiencies, and operation cost holds promise for a sustainable UR-GUV solution for minimizing infection risk in public spaces.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.