The effects of desk-partition layout on cough droplet dynamics relating to seasonal influenza

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(1)

Published: Jan. 1, 2024

The use of physical dividers as control measures for short-range viral transmission in indoor settings has gained increasing attention. However, the understanding regarding their correct usage under different seating arrangements is incomplete. In this study, we focused on assessing effectiveness impeding transient cough droplets three representative layouts using large-eddy simulation technique with Eulerian–Lagrangian model. We computationally also investigated effects ventilation droplet desk-divider layouts. approach was tested two rates (1.0 and 1.8 m/s). A comparative analysis flow fields, topologies, particle directions been studied. findings indicate that sitting arrangements, rates, partition play a significant role designing effective infection office setup considered. protected occupied zone (POV) worked best situations low m/s) cross-partition protecting healthy persons. addition, POV performed well high (1.8 face-to-face layout. side-by-side configuration poorly considered person seated directly opposite infected person. numerical predictions may be used to validate other experimental studies educate workers engineers airborne control.

Language: Английский

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The effects of ventilation conditions on mitigating airborne virus transmission

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(1)

Published: Jan. 1, 2024

The effects of ventilation strategies on mitigating airborne virus transmission in a generic indoor space representative lobby area or information desk found hotel, company, cruise ship are presented. Multiphase computational fluid dynamics simulations employed conjunction with evaporation modeling. Four different flow rates examined based the most updated post-COVID-19 pandemic standards from health organizations and recent findings research studies. Three air changes per hour provide best option for minimizing droplet spreading at reasonable energy efficiency. Thus, higher rate is not solution to avoid diseases. Simultaneous coughing all occupants revealed that contagious droplets could be trapped regions low airflow furniture, significantly prolonging their time. can help define reduce mitigate while maintaining adequate lower consumption. present work impacts how heat, air-conditioning, systems designed implemented.

Language: Английский

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Unsupervised machine learning of virus dispersion indoors

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(1)

Published: Jan. 1, 2024

This paper concerns analyses of virus droplet dynamics resulting from coughing events within a confined environment using, as an example, typical cruiser's cabin. It is paramount importance to be able comprehend and predict dispersion patterns enclosed spaces under varying conditions. Numerical simulations are expensive difficult perform in real-time situations. Unsupervised machine learning methods proposed study patterns. Data multi-phase computational fluid at different flow rates utilized with unsupervised algorithm identify prevailing trends based on the distance traveled by droplets their sizes. The determines optimal clustering introducing novel metrics such Clustering Dominance Index Uncertainty. Our analysis revealed existence three distinct stages for during event, irrespective underlying rates. An initial stage where all disperse homogeneously, intermediate larger overtake smaller ones, final ones. first time coupled particles' understand dynamic behavior.

Language: Английский

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Ultra-scaled deep learning temperature reconstruction in turbulent airflow ventilation

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(6)

Published: June 1, 2024

A deep learning super-resolution scheme is proposed to reconstruct a coarse, turbulent temperature field into detailed, continuous field. The fluid mechanics application here refers an airflow ventilation process in indoor setting. Large eddy simulations are performed from dense simulation grid and provide data two-dimensional images. images fed flow reconstruction model after being scaled down 100 times. Training testing on these images, the learns map such highly coarse fields their high-resolution counterparts. This computational, approach mimics of employing sparse sensor measurements trying upscale Notably, achieves high performance when input by 5–20 times original dimension, acceptable 30, poor at higher scales. peak signal-to-noise ratio, structure similarity index, relative error between reconstructed output given compared common image processing techniques, as linear bicubic interpolation. pipeline suggests high-performance platform that calculates spatial values can bypass installation wide array, making it cost-effective solution for relevant applications.

Language: Английский

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Infectious cough droplet dynamics in a makeshift hospital isolation ward

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(2)

Published: Feb. 1, 2025

The COVID-19 pandemic highlighted the need for rapidly deployable healthcare facilities, leading to increased use of modular construction methods. Nonetheless, knowledge about airflow patterns and spread bioaerosols in these wards remains insufficient, potentially heightening risk cross-infection among workers patients. This paper presents a ventilation design negative-pressure ward aimed at reducing infectious particles. We investigate effects various designs, patient postures (sitting supine), air changes per hour (ACH) on cough droplets an airborne infection isolation room using large eddy simulation Eulerian–Lagrangian model. Findings show that ceiling exhaust grilles (design 2) resulted lowest radial dispersion (3.64 m) 12 ACH, while sidewall exhausts (baseline) performed best higher ACH levels. Seated patients had quicker droplet evaporation compared those supine position. setups survival included bed's bottom ceiling, maintaining minimum ACH. Cases 5 13, with over patient's head bottom, showed concentrations DPM, under 0.008 km−3 near source less than 0.001 mid-room. Sitting posture consistently led lower DPM concentrations. research emphasizes critical role placement re-circulation transmission risks, ultimately contributing improved strategies control AII rooms.

Language: Английский

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The corridor effect in droplet and aerosol pathogens transmission

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(3)

Published: March 1, 2025

This study investigates the effect of natural ventilation on distribution airborne pathogens in narrow, low-ceiling corridors typical hotels, offices, or cruise ships. Two scenarios are examined: a milder cough at 6 m/s and stronger 12 m/s. A reference baseline case with no airflow is compared to cases featuring an incoming velocity 1 (3.6 km/h), examining differences dispersal respiratory droplets from two individuals coughing spaced 5 meters apart. Both direction airflow, assuming one-way traffic minimize pathogen transmission. Findings indicate that accelerates past door, exceeding 3 m/s, gusts reaching 4 due interaction recirculation zones. acceleration affects droplet dispersal. Larger (>150 μm) maintain ballistic trajectory, traveling 2–4 m, potentially increasing transmission risk but suggesting 5-m distancing policy could suffice for protection. Smaller (<150 μm), especially those <100μm, spread extensively regardless strength while containing most viral mass overall. Thus, alone insufficient. The recommends additional safety measures be enforced, such as wearing masks, stricter usage protocols by limiting corridor use one person every 20–30 s, eliminating when feasible effectively mitigate risks environments.

Language: Английский

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Sparsity and mixing effects in deep learning predictions of temperature and humidity

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(8)

Published: Aug. 1, 2024

Developing deep learning models for predicting environmental data is a powerful tool that can significantly enhance equipment design, optimize the implementation of engineering systems, and deepen our understanding limitations imposed by flow physics. This study unequivocally demonstrates accuracy forecasting based on popular algorithms, such as long-short-term memory model, in turbulent mixing regions associated with physics arising from ventilation. contingent two essential conditions. First, sparsity sampling consistent model's overall. Second, ensures reasonable regions. The investigation combines high-resolution simulation predictions velocity, temperature, relative humidity ventilated confined space. results this study, their high accuracy, not only help to understand circulation but also pave way developing predictive capabilities data.

Language: Английский

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On particle dispersion statistics using unsupervised learning and Gaussian mixture models

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(9)

Published: Sept. 1, 2024

Understanding the dispersion of particles in enclosed spaces is crucial for controlling spread infectious diseases. This study introduces an innovative approach that combines unsupervised learning algorithm with a Gaussian mixture model to analyze behavior saliva droplets emitted from coughing individual. The effectively clusters data, while captures distribution these clusters, revealing underlying sub-populations and variations particle dispersion. Using computational fluid dynamics simulation this integrated method offers robust, data-driven perspective on dynamics, unveiling intricate patterns probabilistic distributions previously unattainable. combined significantly enhances accuracy interpretability predictions, providing valuable insights public health strategies prevent virus transmission indoor environments. practical implications are profound, as it demonstrates potential advanced techniques addressing complex biomedical engineering challenges underscores importance coupling sophisticated algorithms statistical models comprehensive data analysis. impact findings significant, highlighting relevance research real-world applications.

Language: Английский

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Integrated infection and crowd behaviour model for COVID-19 infection risk assessment onboard large passenger vessels

IMDC., Journal Year: 2024, Volume and Issue: unknown

Published: May 21, 2024

The development of the global COVID-19 pandemic from 2020 onward has had significant impact on world and specifically maritime industry. Striking examples were outbreaks onboard Diamond Princess cruise vessel U.S.S. Theodore Roosevelt aircraft carrier at start pandemic. Contagious disease management large passenger ships remains a complex issue, amplified by international character industry, confined environment shared facilities. This paper therefore presents an integrated infection crowd behavior model used to calculate agent-specific risk, incorporating guest crew circulation through ship layout. is investigate effect layout design, capacity reduction mask wearing airborne risk vessels.

Language: Английский

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Close Contact Tracing and Risky Area Identification Using Alpha Shape Algorithm and Binary Contact Detection Model Based on Bluetooth 5.1

Journal of ETA Maritime Science, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 16, 2024

This study presents a novel approach to managing disease outbreaks on cruise ships by integrating Bluetooth 5.1 technology, Binary Contact Detection Model, and an Alpha Shape algorithm.By harnessing the precise data capture capabilities of 5.1, this accurately tracks interpersonal interactions delineated high-risk areas, effectively enhancing close contact tracing surveillance efforts.The Model utilizes In-phase (I) Quadrature (Q) identify contacts with high accuracy, while algorithm helps in mapping out areas most susceptible transmission.The combined use these technologies represents significant advancement public health surveillance, offering method enhance safety mitigate spread infections ships.

Language: Английский

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