A recent breakout of the COVID-19 pandemic inspired researchers to find ideal solutions for removing SARS-CoV-2 from indoor air. In-duct ultraviolet germicidal irradiation was employed in rooms with heating, ventilation, and air conditioning (HVAC) systems to stop the spread of COVID-19. The current investigation introduces Bunimovich stadium-inspired flow channels inside the square-shaped duct. The impact of the Bunimovich channel shape on light distribution is studied and compared with the traditional rectangular-shaped duct. The core of the Bunimovich channel is a square with δ and γ equal to 0.5. A semi-circle surrounds the square's left and right sides. The air velocity in the HVAC system with the Bunimovich channels varies from 10 m/s to 15 m/s, resulting in variation in aerosol particles’ residence period in front of the ultraviolet-C (UVC) source. The Bunimovich channel delivered better UVC irradiance uniformity than a rectangular duct. The uniformity ratio for the Bunimovich channel was 0.788 compared to 0.6949 for the rectangular duct. The UVC dose delivered by the source in the Bunimovich channel varies from 1.48 mJ/cm2 to 3.03 mJ/cm2. The delivered dose is higher than the required 1.2 mJ/cm2 dose for log-4 reduction (i.e. 99.99%).
NoorimotlaghZJaafarzadehNSilvaS. A systematic review of possible airborne transmission of the COVID-19 virus (SARS-CoV-2) in the indoor air environment. Environ Res 2021; 193. Epub ahead of print 2020. DOI: 10.1016/j.envres.2020.110612.
YuHCMuiKWWongLT, et al.Ventilation of general hospital wards for mitigating infection risks of three kinds of viruses including Middle East respiratory syndrome coronavirus. Indoor Built Environ2017; 26: 514–527.
6.
LiYHuangXYuITS, et al.Role of air distribution in SARS transmission during the largest nosocomial outbreak in Hong Kong. Indoor Air2005; 15: 83–95.
7.
ReedNG. The history of ultraviolet germicidal irradiation for air disinfection. Public Health Rep 2021; 125: 15–27. DOI:10.1177/003335491012500105.
8.
WellsWFFairGM. Viability of B. coli exposed to ultra-violet radiation in air. Science (80-)1935; 82: 280–281.
9.
SuCLauJGibbsSG. Student absenteeism and the comparisons of two sampling procedures for culturable bioaerosol measurement in classrooms with and without upper room ultraviolet germicidal irradiation devices. Indoor Built Environ2016; 25: 551–562.
10.
GilkesonCANoakesCJKhanMAI. Computational fluid dynamics modelling and optimisation of an upper-room ultraviolet germicidal irradiation system in a naturally ventilated hospital ward. Indoor Built Environ2014; 23: 449–466.
11.
KanaanMGhaddarNGhaliK, et al.New airborne pathogen transport model for upper-room UVGI spaces conditioned by chilled ceiling and mixed displacement ventilation: enhancing air quality and energy performance. Energy Convers Manag2014; 85: 50–61.
12.
NoakesCJBeggsCBSleighPA. Modelling the performance of upper room ultraviolet germicidal irradiation devices in ventilated rooms: comparison of analytical and CFD methods. Indoor Built Environ2004; 13: 477–488.
13.
NoakesCJSleighPAFletcherLA, et al.Use of CFD modelling to optimise the design of upper-room UVGI disinfection systems for ventilated rooms. Indoor Built Environ2006; 15: 347–356.
14.
NoakesCJFletcherLABeggsCB, et al.Development of a numerical model to simulate the biological inactivation of airborne microorganisms in the presence of ultraviolet light. J Aerosol Sci2004; 35: 489–507.
15.
LimHSKimG. Spectral characteristics of UV light existing in indoor visual environment. Indoor Built Environ2010; 19: 586–591.
16.
BolashikovZDMelikovAK. Methods for air cleaning and protection of building occupants from airborne pathogens. Build Environ2009; 44: 1378–1385.
17.
DarnellMERSubbaraoKFeinstoneSM, et al.Inactivation of the coronavirus that induces severe acute respiratory syndrome, SARS-CoV. J Virol Methods2004; 121: 85–91.
18.
CattaiFD’OrazioASbardellaG. A systematic review on the application of ultraviolet germicidal irradiation to HVAC systems. Energies2023; 16: 7569.
19.
WangBMortazaviRHaghighatF. Evaluation of modeling and measurement techniques of ultraviolet germicidal irradiation effectiveness — towards the design of immune buildings. Indoor Built Environ2009; 18: 101–112.
20.
BeggsCBKerrKGDonnellyJK, et al.An engineering approach to the control of Mycobacterium tuberculosis and other airborne pathogens: a UK hospital based pilot study. Trans R Soc Trop Med Hyg2000; 94: 141–146.
21.
BunimovichLA. On ergodic properties of certain billiards. Funct Anal Its Appl1974; 8: 254–255.
22.
ChernovNMarkarianR. Chaotic Billiards. Mathematic. American Mathematical Society, 2006.
LopacVMrkonjićIPavinN, et al.Chaotic dynamics of the elliptical stadium billiard in the full parameter space. Phys D Nonlinear Phenom2006; 217: 88–101.
25.
MishraSSinghDWanareH. Chaotic cavity design of a UV-C disinfection chamber for uniform radiation distribution. Appl Opt2022; 61: 890.
Rajkhowa S. Chapter 9 - Heat, solar pasteurization, and ultraviolet radiation treatment for removal of waterborne pathogens. In: Vara Prasad MN and Grobelak ABT-WP (eds)Waterborne Pathogens. Butterworth-Heinemann, 2020, pp.169–187. DOI: 10.1016/B978-0-12-818783-8.00009-8.
28.
LuoHZhongL. Ultraviolet germicidal irradiation (UVGI) for in-duct airborne bioaerosol disinfection: review and analysis of design factors. Build Environ2021; 197: 107852.
ChiaPYColemanKKTanYK, et al.Detection of air and surface contamination by SARS-CoV-2 in hospital rooms of infected patients. Nat Commun2020; 11. Epub ahead of print 2020. DOI: 10.1038/s41467-020-16670-2.
31.
Bar-OnYMFlamholzAPhillipsR, et al.SARS-CoV-2 (COVID-19) by the numbers. Elife2020; 9. Epub ahead of print 2 April 2020. DOI: 10.7554/eLife.57309.
32.
SasgesMRobinsonJDaynouriF. Ultraviolet lamp output measurement: a concise derivation of the Keitz equation. Ozone Sci Eng2012; 34: 306–309.
33.
KumarVBishtDSGargH. Modeling a UVC irradiation standalone system for inactivating Mycobacterium tuberculosis from indoor spaces. Appl Opt2023; 62: 6652.
34.
Singh BishtDKumarVSinghS, et al.Computational analysis and optimization of daylight collector geometry for removal of hotspots in circular mirror light pipe. Sol Energy2023; 264: 112066.
35.
SharmaKKumarVBishtDS, et al.Comparative study of acrylic flat plate and dome shaped collector for summer and winter solstice conditions. Mater Today Proc2021; 45: 5489–5493.
36.
GargHBishtDSharmaK, et al.Analysis, evaluation and integration of modular natural illumination system using a rectangular Fresnel lens for high performance. Light Res Technol 2023; 55: 554–570. DOI: 10.1177/14771535211063624.
37.
Kumar V, Sharma K, Bisht DS, et al. Optimum concentration ratio for plastic optical fiber-based Fresnel lens daylighting system. In: Jain VK, Gomes C and Verma A (eds) Renewable energy and storage devices for sustainable development. Singapore: Springer, Singapore, 2022, pp.169–179. DOI: 10.1007/978-981-16-9280-2_21.
38.
Bisht DS, Garg H, Shravana Kumar RR, et al. Study and analysis of parameters affecting tubular daylighting device. In: Jain VK, Kumar V and Verma A (eds) Advances in solar power generation and energy harvesting. Singapore: Springer Singapore, 2020, pp.73–92. DOI: 10.1007/978-981-15-3635-9_9.
39.
SinghGSharmaKMehtaJS, et al.Enhanced daylight system with acrylic based collimator. Mater Today Proc2020; 28: 1996–2002.
40.
BishtDSSinghSSharmaK, et al.Performance analysis of a passive tubular skylight using rectilinear parabolic-profile integrated with plane reflectors and wedge prism. Sol Energy2021; 222: 235–258.
41.
BishtDGargHShravana KumarR, et al.Enhancing the performance of a passive tubular daylighting device using a parabolic-profile collector. Light Res Technol2020; 52: 495–523.
KumarVBishtDSGargH. Mean wavelength-based Fresnel lens solar collector for eliminating the hotpot problem in daylighting systems. Appl Opt2023; 62: 9188.
44.
KumarVBishtDGargH. Design, analysis and validation of Customised Homocentric Fresnel Collector based on longest wavelength of visible spectrum. Light Res Technol2023. Epub ahead of print 13 November 2023. DOI: 10.1177/14771535231207099.
45.
WrightNGHargreavesDM. The use of CFD in the evaluation of UV treatment systems. J Hydroinformatics2001; 3: 59–70.
46.
RaeiszadehMAdeliB. A critical review on ultraviolet disinfection systems against COVID-19 outbreak: applicability, validation, and safety considerations. ACS Photonics2020; 7: 2941–2951.
47.
Sesti-CostaRNegrão C vonZShimizuJF, et al.UV 254 Nm is more efficient than UV 222 nm in inactivating SARS-CoV-2 present in human saliva. Photodiagnosis Photodyn Ther2022; 39: 1–8.
48.
WalkerCMKoG. Effect of ultraviolet germicidal irradiation on viral aerosols. Environ Sci Technol2007; 41: 5460–5465.
49.
GargAHRingeRPDasS, et al.UVC-based air disinfection system for rapid inactivation of SARS- CoV-2 present in the air. Pathogens 2023; 12: 419. DOI: 10.3390/pathogens12030419
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