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Identification of probabilistic size of breathing zone during single inhalation phase in semi-outdoor environmental scenarios

مؤلف البحث
Islam M.S. Abouelhamd, Kuga, K., Yoo, S.-J. and Ito, K.
المشارك في البحث
تاريخ البحث
سنة البحث
2023
مجلة البحث
Building and Environment
الناشر
Elsevier
عدد البحث
243
تصنيف البحث
Q1
صفحات البحث
p.110672.
موقع البحث
https://doi.org/10.1016/j.buildenv.2023.110672
ملخص البحث

This study investigates outdoor public health by predicting the airflow fields and probabilistic size of breathing zones. Computational fluid dynamics (CFD) simulations were performed in a simplified semi-outdoor domain, utilizing a validated computer-simulated person (CSP) with an integrated nasal cavity. The simulations were conducted for eight wind orientations (0◦, 90◦, 180◦, 270◦, 45◦, 135◦, 225◦, and 315◦), four wind velocities (Uref = 0.25, 0.5, 0.75, and 1.0 m/s), and one inhalation flow rate (18.7 L/min), considering both steady and transient conditions. The RANS-based equations were solved using the SST k-omega turbulence model. Breathing zones were computed and visualized using the scale for ventilation efficiency 5 (SVE5) and reverse time-traced vector techniques. The results indicated that wind orientation influenced the air velocity, temperature, and breathing zone distribution. The steady-state condition tended to overestimate breathing zones, whereas, under transient conditions, they assumed a semi-cylindrical form that extended horizontally, with a slight slope from the nostrils towards the direction of the wind source. The horizontal extension of the breathing regions increased at high wind speeds and with a smaller cylinder radius compared to calm conditions. Eventually, this study proposed new definitions of the breathing zone in the semi-outdoor environment in different SVE5 values. These findings can contribu

Research Rank
International Journal