The project uses as a prototype model used by NASA (patent number US 8,328,917 B2 [8]) that filtrates and treats the air, removing airborne particles, volatile organic compounds (VOC), and biomolecules. Equipment that could be used at home or hospital rooms was developed using the same air treatments and additionally removing CO2 concentration. The additional operation is necessary due to the increase of CO2 caused by the bad ventilation and recirculation of air in indoor ambient.
To reduce operation costs and increase the lifetime of the equipment, the actuation of the equipment is controlled by the indoor concentration of aerosols. Since open-source data about atmospheric aerosols is available to the public, the group created a model capable to estimate the concentration of the contaminant that infiltrates in an indoor area in real-time. Through this system, the aerosol concentration is maintained below limits of indoor air quality standards, achieving a better quality of life of the individuals, and avoiding the spread of airborne diseases.
The world is experiencing the biggest pandemic of the century, which already killed thousands of people. Never before, so many world nations work together to develop solutions to combat and mitigate a problem. As the coronavirus is a pathogen of nanometric dimensions, it is very easy to be carried through the air during the emission of bioaerosols generated during speeches, coughing or sneezing, and other particles in the air [5-7]. On the other hand, people spend more time at home, due to the lockdown policies, which implies a greater exposure to air contaminants produced by organisms [12]. In this way, our group was inspired by this huge effort and tried to propose a solution that would reduce the exposure of people in indoor environments with a high concentration of pathogens as well as other airborne contaminants. We propose the development of small equipment - but scalable - in order to filter the air in badly ventilated environments such as hospital rooms, surgery rooms, bedrooms, gyms, or any other indoor environment with high traffic of people. We used as inspiration the Air Revitalization System (ARS) used by NASA to supply and purify the air from the International Space Station (ISS). By use of available ARS information and many open-source data, including climate data from the NASA website, we propose a device that contains modular steps to clean the indoor air and remove CO2 gas. The equipment is capable to eliminate aerosols, microorganisms such as COVID-19, and contaminants like volatile organic compounds. A sketch was built using a 3D modeling Sketchup software to illustrate the concept of the equipment, and a simplified CFD study of the indoor airflow was performed, based on an Eulerian approach using the open-source platform OpenFOAM [13].
Video link:
https://youtu.be/7aSWjenf-sw
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9. Life Support Systems; Available onlinehttps://www.nasa.gov/content/life-support-systems; Accessed on May, 30th, 2020;
10. Clearing the Air in Space: Improving Life Support on International Space Station and For Deep Space Exploration; Available onlinehttps://www.nasa.gov/mission_pages/station/research/long_duration_sorbent_testbed; Accessed on May, 30th, 2020;
11. Home Air Purifiers Eradicate Harmful Pathogens; Available onlinehttps://spinoff.nasa.gov/Spinoff2013/cg_4.html; Accessed on May, 30th, 2020;
12. NASA Air Quality Analysis of the COVID-19 Pandemic; Available onlinehttps://airquality.gsfc.nasa.gov/; Accessed on May, 30th, 2020;
13. Deshpande, S. S, Anomolu, L., Trujillo, M. F., 2012. Evaluating the performance of the two-phase flow solver interFoam. Computational Science & Discovery 5. doi:10.1088/1749-4699/5/1/014016
14. Friedrich, R., 2017. Chapter 6: Exposure Modelling. Air Quality Management. University of Stuttgart.