شبیه‌سازی عددی دو عطسه متوالی انسان و بررسی پخش و نفوذ قطرات حاصل از آن در محیط اطراف

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده مهندسی مکانیک، دانشگاه تربیت مدرس، تهران، ایران

چکیده

در مطالعه حاضر، با شبیه‌سازی فرایند دو عطسه متوالی با استفاده از مدل واقعی راه هوایی فوقانی یک مرد ۶۵ ساله غیرسیگاری، الگوی پراکندگی قطرات حاصل از فرایند دو عطسه متوالی مورد بررسی و تحلیل قرار گرفته است. با استفاده از دینامیک سیالات محاسباتی، سرعت جریان هوا در هنگام دو عطسه متوالی بررسی شده و از مدل آشفتگی k-ω SST به‌منظور بررسی جریان استفاده شده است. با فرض تغییرات دبی جریان به‌صورت واقع‌گرایانه و یکسان در هر دو عطسه، بیشینه دبی عبوری در هنگام عطسه بر اساس سن و جنسیت سوژه برابر ۵۵۳ لیتر بر دقیقه است. در مطالعه حاضر، شبیه‌سازی با درنظرگرفتن طیف گسترده‌ای از قطرات با قطرهای ۱ تا ۱۰۰۰ میکرون انجام شده است و حدود ۲ میلیون قطره در طی فرایند دو عطسه متوالی در محیط اطراف تزریق شده است. در این مطالعه دما هوای موجود در محیط اطراف و جت هوای خروجی از درون دستگاه تنفسی به ترتیب برابر ۲۴ و ۳۵ درجه سانتی‌گراد و رطوبت نسبی محیط اطراف و جت هوا به ترتیب برابر ۶۵ و ۹۵ درصد فرض شده است. بیشینه میزان نفوذ و پخش قطرات حاصل از دو عطسه متوالی در زمان ۵ ثانیه به ترتیب 19/9 و 7/5 درصد بیشتر از میزان نفوذ و پخش قطرات حاصل از تک عطسه معمولی در زمان مشابه است. بخش عمده‌ای از قطرات تزریق شده در محیط اطراف در طول فرایند دو عطسه متوالی تبخیر شده‌اند؛ به‌طوری که در زمان ۵ ثانیه کمتر از 40 هزار قطره در محیط باقی مانده‌اند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical simulation of two consecutive human sneezing and examining the dispersion of the resulting droplets in the surroundings

نویسندگان [English]

  • Alireza Zandaf
  • Ghassem Heidarinejad
Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran
چکیده [English]

In the present study, by simulating the process of two consecutive sneezes using a real model of the upper airway of a 65-year-old non-smoking man, the dispersion pattern of droplets resulting from the process of two consecutive sneezes has been investigated. Using computational fluid dynamics, the velocity of airflow during two consecutive sneezes was checked and the k-ω SST turbulence model was used to check the flow. Assuming realistic flow rate changes in both sneezes, the maximum flow rate during sneezing according to the subject's age and gender is equal to 553 L/min. In the present study, the simulation has been carried out by considering a wide range of droplets with diameters of 1 to 1000 microns, and about 2 million drops have been injected into the surrounding environment during the process of two consecutive sneezes. In this study, the temperature of the air in the surrounding environment and the air jet coming out of the respiratory system are assumed to be 24 and 35 degrees Celsius, and the relative humidity of the surrounding environment and the air jet is assumed to be 65 and 95%. The maximum rate of penetration and spread of droplets resulting from two consecutive sneezes in 5 seconds is 19.9 and 7.5% higher than the rate of penetration and distribution of droplets resulting from a single normal sneeze at the same time. Most of the injected droplets have evaporated in the surrounding environment during the process of two consecutive sneezes, and less than 40,000 drops are left in the environment in 5 seconds.

کلیدواژه‌ها [English]

  • Numerical simulation of Sneezing
  • consecutive sneezing
  • droplet diffusion
  • Two-Phase Flow
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