Air curtains is promising in reducing the short-range infection risk in hospitals. To quantitatively evaluate its performance, this paper explores air curtains equipped on normal consulting desk to avoid doctor’s direct exposure to the patient exhaled pollutants. A numerical investigation is conducted to evaluate the effects of supply air velocity and angle on cutting off performance. Simulation results show that the average mass fraction of exhaled pollutants decreases significantly (70%–90%) in the consulting ward, indicating satisfying performance of air curtains. Increasing supply air velocity is demonstrated to be conducive in forming full air curtains, whereas an excessively high supply air velocity may be of adverse effects by entraining exhaled flow. Besides, the supply air angle is also critical due to its coupling with supply air velocity. It is found that larger angle (0°–40°) is better where velocity is less than 3 m/s, otherwise a small angle (20°) is preferable where velocity is larger than 3 m/s. Exhaled flow could be well suppressed at the supply air angle 20° but moves over air curtains at 40°. This study can provide effective and intuitive guidance in applying air curtains in consulting wards.
Amin M, Dabiri D, Navaz HK (2011). Comprehensive study on the effects of fluid dynamics of air curtain and geometry, on infiltration rate of open refrigerated cavities. Applied Thermal Engineering, 31: 3055–3065.
Cao Z, Han H, Gu B (2011). A novel optimization strategy for the design of air curtains for open vertical refrigerated display cases. Applied Thermal Engineering, 31: 3098–3105.
Cao G, Sirén K, Kilpeläinen S (2014). Modelling and experimental study of performance of the protected occupied zone ventilation. Energy and Buildings, 68: 515–531.
Cao G, Nielsen PV, Jensen RL, Heiselberg P, Liu L, Heikkinen J (2015). Protected zone ventilation and reduced personal exposure to airborne cross-infection. Indoor Air, 25: 307–319.
Eames I, Tang JW, Li Y, Wilson P (2009). Airborne transmission of disease in hospitals. Journal of the Royal Society Interface, 6 (supply 6): S697–S702.
Ferkol T, Schraufnagel D (2014). The global burden of respiratory disease. Annals of the American Thoracic Society, 11: 404–406.
Gil-Lopez T, Castejon-Navas J, Galvez-Huerta MA, O’Donohoe PG (2014). Energetic, environmental and economic analysis of climatic separation by means of air curtains in cold storage rooms. Energy and Buildings, 74: 8–16.
Goubran S, Qi D, Wang LL (2017). Assessing dynamic efficiency of air curtain in reducing whole building annual energy usage. Building Simulation, 10: 497–507.
Inouye S, Matsudaira Y, Sugihara Y (2006). Masks for influenza patients: measurement of airflow from the mouth. Japanese Journal of Infectious Diseases, 59: 179–181.
Ji Y, Qian H, Ye J, Zheng X (2018). The impact of ambient humidity on the evaporation and dispersion of exhaled breathing droplets: A numerical investigation. Journal of Aerosol Science, 115: 164–172.
Laguerre O, Hoang MH, Osswald V, Flick D (2012). Experimental study of heat transfer and air flow in a refrigerated display cabinet. Journal of Food Engineering, 113: 310–321.
Li Y, Huang X, Yu ITS, Wong TW, Qian H (2005). Role of air distribution in SARS transmission during the largest nosocomial outbreak in Hong Kong. Indoor Air, 15: 83–95.
Lidwell OM, Williams REO (1961). The epidemiology of the common cold. I. Journal of Hygiene, 59: 309–319.
Liu L, Wei J, Li Y, Ooi A (2017a). Evaporation and dispersion of respiratory droplets from coughing. Indoor Air, 27: 179–190.
Liu L, Li Y, Nielsen PV, Wei J, Jensen RL (2017b). Short-range airborne transmission of expiratory droplets between two people. Indoor Air, 27: 452–462.
Liu F, Zhang C, Qian H, Zheng X, Nielsen PV (2019). Direct or indirect exposure of exhaled contaminants in stratified environments using an integral model of an expiratory jet. Indoor Air, 29: 591–603.
MacIntyre CR, Wang Q, Seale H, Yang P, Shi W, et al. (2013). A randomized clinical trial of three options for N95 respirators and medical masks in health workers. American Journal of Respiratory and Critical Care Medicine, 187: 960–966.
MacIntyre CR, Seale H, Dung TC, Hien NT, Nga PT, Chughtai AA, Rahman B, Dwyer DE, Wang Q (2015). A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ Open, 5: e006577.
MacIntyre CR, Zhang Y, Chughtai AA, Seale H, Zhang D, Chu Y, Zhang H, Rahman B, Wang Q (2016). Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness. BMJ Open, 6: e012330.
Nielsen PV, Buus M, Winther F, Thilageswaran M (2008). Contaminant flow in the microenvironment between people under different ventilation conditions. ASHRAE Transactions, 114(2): 632–638.
Novel Coronavirus Pneumonia Emergency Response Epidemiology Team (2020). Epidemiological and clinical features of the 2019 novel coronavirus outbreak in China. Chinese Journal of Epidemiology, 41: 145–151. (in Chinese)
Saarinen P, Kalliomäki P, Koskela H, Tang JW (2018). Large-eddy simulation of the containment failure in isolation rooms with a sliding door—An experimental and modelling study. Building Simulation, 11: 585–596.
Shih YC, Yang AS, Lu C (2011). Using air curtain to control pollutant spreading for emergency management in a cleanroom. Building and Environment, 46: 1104–1114.
Tang JW, Liebner TJ, Craven BA, Settles GS (2009). A schlieren optical study of the human cough with and without wearing masks for aerosol infection control. Journal of the Royal Society Interface, 6(suppl_6): S727–S736.
Topp C, Nielsen PV, Sørensen DN (2002). Application of computer simulated persons in indoor environmental modeling/Discussion. ASHRAE Transactions, 108(2): 1084–1090.
Versteeg HK, Malalasekera W (2007). An Introduction to Computational Fluid Dynamics: The Finite Volume Method, 2nd edn. New York: Pearson Education.
Wei J, Li Y (2015). Enhanced spread of expiratory droplets by turbulence in a cough jet. Building and Environment, 93: 86–96.
WHO (2020). Coronavirus disease (COVID-2019) situation reports. World Health Organization. Available at https://www.who.int/docs/default-source/coronaviruse/situation-reports.
Xie X, Li Y, Chwang ATY, Ho PL, Seto WH (2007). How far droplets can move in indoor environments? Revisiting the Wells evaporation-falling curve. Indoor Air, 17: 211–225.
Zhai ZJ, Zhang Z, Zhang W, Chen QY (2007). Evaluation of various turbulence models in predicting airflow and turbulence in enclosed environments by CFD: Part 1—Summary of prevalent turbulence models. HVAC&R Research, 13: 853–870.
Zhao F, Shen G, Liu K, Xu Y, Liu D, Wang H (2018). Room airborne pollutant separation by the use of air curtains in the large building enclosure: Infiltration efficiency and partial enclosure ventilation rate. Journal of Building Engineering, 18: 386–394.
Zhou Q, Qian H, Ren H, Li Y, Nielsen PV (2017). The lock-up phenomenon of exhaled flow in a stable thermally-stratified indoor environment. Building and Environment, 116: 246–256.
This work is jointed supported by the National Natural Science Foundation of China (No. 51778128), the National Key Research and Development Program of China (No. 2018YFC1200100), the Entrepreneurship Leadership Project in Guangzhou Development Zone of China (No. CY2018-003), and the Scientific Research Foundation of Graduate School of Southeast University (No. YBPY1903).
About this article
Cite this article
Ye, J., Qian, H., Ma, J. et al. Using air curtains to reduce short-range infection risk in consulting ward: A numerical investigation. Build. Simul. 14, 325–335 (2021). https://doi.org/10.1007/s12273-020-0649-7
- air curtains
- consulting ward
- cutting off performance
- numerical investigation