Version 1
: Received: 6 November 2024 / Approved: 6 November 2024 / Online: 7 November 2024 (11:22:07 CET)
How to cite:
Barari, K.; Si, X.; Hajian, R.; Xi, J. Top and Side Leakage Effects on Thermoregulation and Moisture Retention with Facemask Wearing. Preprints2024, 2024110485. https://doi.org/10.20944/preprints202411.0485.v1
Barari, K.; Si, X.; Hajian, R.; Xi, J. Top and Side Leakage Effects on Thermoregulation and Moisture Retention with Facemask Wearing. Preprints 2024, 2024110485. https://doi.org/10.20944/preprints202411.0485.v1
Barari, K.; Si, X.; Hajian, R.; Xi, J. Top and Side Leakage Effects on Thermoregulation and Moisture Retention with Facemask Wearing. Preprints2024, 2024110485. https://doi.org/10.20944/preprints202411.0485.v1
APA Style
Barari, K., Si, X., Hajian, R., & Xi, J. (2024). Top and Side Leakage Effects on Thermoregulation and Moisture Retention with Facemask Wearing. Preprints. https://doi.org/10.20944/preprints202411.0485.v1
Chicago/Turabian Style
Barari, K., Rozhin Hajian and Jinxiang Xi. 2024 "Top and Side Leakage Effects on Thermoregulation and Moisture Retention with Facemask Wearing" Preprints. https://doi.org/10.20944/preprints202411.0485.v1
Abstract
Mask-wearing-induced discomfort often leads to unconscious loosening of the mask to relieve the discomfort, thereby compromising its protective efficacy. This study investigated how leakage flows affect mask-associated thermoregulation and vapor trapping to inform better mask designs. An integrated ambience-mask-face-airway model with various mask-wearing misfits was developed. The transient warming/cooling effects, thermal buoyancy force, tissue heat generation, vapor phase change, and fluid/heat/mass transfer through a porous medium were considered in this model, which was validated using Schlieren imaging, a thermal camera, and velocity/temperature measurements. Leakages from the top and side of the mask were analyzed in comparison to a no-leak scenario under cyclic respiration conditions. Results showed a significant inverse relationship between mask leakage and facial skin temperature/humidity. An equivalent impact from buoyancy forces and exhalation flow inertia was observed both experimentally and numerically, indicating a delicate balance between natural convection and forced convection that is sensitive to leakage flows and critical in thermo-humidity regulation. For a given gap, the leakage fraction was not constant within one breathing cycle, but constantly increased during exhalation. Persistently higher temperatures were found in the nose region throughout the breathing cycle in a sealed mask and were mitigated during inhalation when gaps were present. Vapor condensation occurred within the mask medium during exhalation in all mask-wearing cases. The thermal and vapor temporal variation profiles were sensitive to the location of the gap, highlighting the feasibility of leveraging temperature and relative humidity to test mask fit and quantify leakage fraction.
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
