Korean Chemical Engineering Research

  • 제60권2호
  • /
  • Pages.282-288
  • /
  • 2022
  • /
  • 0304-128X(pISSN)
  • /
  • 2233-9558(eISSN)
한국화학공학회 (The Korean Institute of Chemical Engineers)
권호 표지
DOI QR코드

DOI QR Code

코로나-19 보호용 페이스 마스크에서의 액적 고속 충돌 거동

Microdroplet Impact Dynamics at Very High Velocity on Face Masks for COVID-19 Protection

  • 최재원 (숭실대학교 기계공학부) ;
  • 이동호 (숭실대학교 기계공학부) ;
  • 어지수 (숭실대학교 기계공학부) ;
  • 이동근 (숭실대학교 기계공학부) ;
  • 강전웅 (숭실대학교 기계공학부) ;
  • 지인서 (숭실대학교 기계공학부) ;
  • 김태영 (숭실대학교 기계공학부) ;
  • 홍지우 (숭실대학교 기계공학부)
  • Choi, Jaewon (School of Mechanical Engineering, Soongsil University) ;
  • Lee, Dongho (School of Mechanical Engineering, Soongsil University) ;
  • Eo, Jisu (School of Mechanical Engineering, Soongsil University) ;
  • Lee, Dong-Geun (School of Mechanical Engineering, Soongsil University) ;
  • Kang, Jeon-Woong (School of Mechanical Engineering, Soongsil University) ;
  • Ji, Inseo (School of Mechanical Engineering, Soongsil University) ;
  • Kim, Taeyung (School of Mechanical Engineering, Soongsil University) ;
  • Hong, Jiwoo (School of Mechanical Engineering, Soongsil University)
  • 투고 : 2021.10.31
  • 심사 : 2021.12.14
  • 발행 : 2022.05.01
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

코로나 팬데믹 시대에서 비말(respiratory droplet)을 통한 감염 및 확산을 막기 위해 마스크는 없어서는 안 될 생활 필수품이 되었다. 본 연구에서는 두 가지 다른 타입의 마스크(KF-94 마스크와 덴탈 마스크)가 비말 차단에 얼마나 효과적인지를 파악하기 위하여, i) 각각의 마스크를 구성하고 있는 필터의 젖음성(wettability) 특성을 분석하고, ii) 필터 표면에 빠른 속도로 충돌하는 미소 액적의 동적 거동 특성을 실험적으로 관찰하였다. 각 필터의 구성 재료에 따라 상반된 젖음성 특성, 소수성(hydrophobicity) 또는 친수성(hydrophilicity)을 보임을 확인하였다. 또한, 일정 체적을 갖는 미소 액적을 안정적으로 토출하는 공압 조건을 탐색하고 액적의 충돌 속도 변화에 따른 액적 충돌 거동 변화를 분석하였다. 마스크를 구성하고 있는 필터의 종류와 액적 충돌 속도에 따라 i) 필터를 통과하지 못하거나(no penetration), ii) 필터에 포획(capture)되거나, iii) 필터를 통과(penetration)하는 등의 다른 충돌 후 거동을 보임을 확인하였다. 이러한 결과들은 비말 차단용 마스크 디자인에 있어 매우 기본적이고 유용한 정보를 제공할 뿐만 아니라, 다양한 다공성 표면에서의 액적 거동에 대한 학문적 연구에도 도움이 될 것으로 판단된다.

Facial masks have become indispensable in daily life to prevent infection and spread through respiratory droplets in the era of the corona pandemic. To understand how effective two different types of masks (i.e., KF-94 mask and dental mask) are in blocking respiratory droplets, i) we preferentially analyze wettability characteristics (e.g., contact angle and contact angle hysteresis) of filters consisting of each mask, and ii) subsequently observe the dynamic behaviors of microdroplets impacting at high velocities on the filter surfaces. Different wetting properties (i.e., hydrophobicity and hydrophilicity) are found to exhibit depending on the constituent materials and pore sizes of each filter. In addition, the pneumatic conditions for stably and uniformly dispensing microdroplets with a certain volume and impacting behaviors associated with the impacting velocity and filter type change are systematically explored. Three distinctive dynamics (i.e., no penetration, capture, and penetration) after droplet impacting are observed depending on the type of filter constituting the masks and droplet impact velocity. The present experimental results not only provide very useful information in designing of face masks for prevention of transmission of infectious respiratory diseases, but also are helpful for academic researches on droplet impacts on various porous surfaces.

키워드

과제정보

이 논문은 2020년도 정부(교육부)의 재원으로 한국연구재단의 지원을 받아 수행된 기초연구사업임(No. 2020R1F1A1066664).

참고문헌

  1. Tang, J. W., Liebner, T. J., Craven, B. A. and Settles, G. S., "A Schlieren Optical Study of the Human Cough with and Without Wearing Masks for Aerosol Infection Control," J. R. Soc. Interface, 6, S727-S736(2009).
  2. Maclntyre, C. R., Cauchemez, S., Dwyer, D. E., Seale, H., Cheung, P., Browne, G., Fasher, M., Wood, J., Gao, Z., Booy, R. and Ferguson, N., "Face Mask Use and Control of Respiratory Virus Transmission in Households," Emerg. Infect. Dis., 15(2), 233-241(2009). https://doi.org/10.3201/eid1502.081167
  3. Hui, D. S., Chow, B. K., Chu, L., Ng, S. S., Lee, N., Gin, T. and Chan, M. T. V., "Exhaled Air Dispersion During Coughing with and Without Wearing a Surgical or N95 Mask," Plos One, 7(12), e50845(2012). https://doi.org/10.1371/journal.pone.0050845
  4. Fischer, E., Fischer, M., Grass, D., Henrion, I., Warren, W. and Westman, E., "Low-cost Measurement of Facemask Efficacy for Filtering Expelled Droplets During Speech," Sci. Adv., 6(36), eabd3083(2020). https://doi.org/10.1126/sciadv.abd3083
  5. Dbouk, T. and Drikakis, D., "On Respiratory Droplets and Face Masks," Phys. Fluids, 32(6), 063303(2020). https://doi.org/10.1063/5.0015044
  6. Verma, S., Dhanak, M. and Frankenfield, J., "Visualizing the Effectiveness of Face Masks in Obstructing Respiratory Jets," Phys. Fluids, 32(6), 061708(2020). https://doi.org/10.1063/5.0016018
  7. Kahler, C. J. and Hain, R., "Fundamental Protective Mechanisms of Face Masks Against Droplet Infections," J. Aerosol Sci., 148, 105617(2020). https://doi.org/10.1016/j.jaerosci.2020.105617
  8. Aydin, O., Emon, B., Cheng, S., Hong, L., Chamorro, L. P. and Saif, M. T. A., "Performance of Fabrics for Home-made Masks Against the Spread of COVID-19 Through Droplets: A Quantitative Mechanistic Study," Extrem. Mech. Lett., 40, 100924(2020). https://doi.org/10.1016/j.eml.2020.100924
  9. Sharma, S., Pinto, R., Saha, A., Chaudhuri, S. and Basu, S., "On Secondary Atomization and Blockage of Surrogate Cough Droplets in Single- and Multilayer Face Masks," Sci. Adv., 7(10), eabf0452(2021). https://doi.org/10.1126/sciadv.abf0452
  10. Sahu, R. P., Sinha-Ray, S., Yarin, A. L. and Pourdeyhimi, B., "Drop Impacts on Electrospun Nanofiber Membranes," Soft Matter, 8(14), 3957-3970(2012). https://doi.org/10.1039/c2sm06744g
  11. Dressaire, E., Sauret, A., Boulogne, F. and Stone, H. A., "Drop Impact on a Flexible Fiber," Soft Matter, 12(1), 200-208(2016). https://doi.org/10.1039/c5sm02246k
  12. Ryu, S., Sen, P., Nam, Y. and Lee, C., "Water Penetration Through a Superhydrophobic Mesh During a Drop Impact," Phys. Rev. Lett., 118(1), 014501(2017). https://doi.org/10.1103/physrevlett.118.014501
  13. Kumar, A., Tripathy, A., Nam, Y., Lee, C. and Sen, P., "Effect of Geometrical Parameters on Rebound of Impacting Droplets on Leaky Superhydrophobic Meshes," Soft Matter, 14(9), 1571-1580 (2018). https://doi.org/10.1039/c7sm02145c
  14. Zhang, G., Quetzeri-Santiago, M. A., Stone, C. A., Botto, L. and Castrejon-Pita, J. R., "Droplet Impact Dynamics on Textiles," Soft Matter, 14(40), 8182-8190(2018). https://doi.org/10.1039/c8sm01082j
  15. Safavi, M. and Nourazar, S. S., "Experimental, Analytical, and Numerical Study of Droplet Impact on a Horizontal Fiber," Int. J. Multiph. Flow., 113, 316-324(2019). https://doi.org/10.1016/j.ijmultiphaseflow.2018.10.018
  16. Sen, U., Roy, T., Chatterjee, S., Ganguly, R. and Megaridis, C. M., "Post-impact Behavior of a Droplet Impacting on a Permeable Metal Mesh with a Sharp Wettability Step," Langmuir, 35(39), 12711-12721(2019). https://doi.org/10.1021/acs.langmuir.9b02486
  17. Gu, W., Yan, S. and Bai, Z., "A Study on a Droplet Impact on a Fiber During Coalescence-separation: Phenomena and Models," Chem. Eng. Sci., 212, 115337(2020). https://doi.org/10.1016/j.ces.2019.115337