A CFD Study on the Design Optimization of Airborne Infection Isolation Room

Abstract

Airborne infection isolation (AII) rooms are used to accommodate patients with highly infectious diseases and keep the released pathogens to limit the risk of cross-infection. This paper proposes a concept for an AII room made from two shipping containers to handle the scarcity of hospital beds when the COVID-19 disease spreads over the world. The proposed system consists of the main isolation room, anteroom, and toilet as well as other functional areas. In addition, the main isolation room was modeled with important components such as a supply air vent, exhaust air, a patient, and a bed. The computational fluid dynamics (CFD) approach based on the finite volume method (FVM) is used to solve the three-dimensional governing equations. The CO2 concentration was used to determine the infectious contaminant concentration of the air in the room. Therefore, the infectious control could be evaluated by the air change per hour (ACH). The numerical results show that the room temperature is maintained at 24°C, which is appropriate for people in the room. The laminar airflow extends downward to the floor after leaving the supply air vent on the ceiling, creating circulating patterns throughout the room. When evaluating the effectiveness of ventilation systems to remove airborne contaminants based on different ACH numbers, the CO2 concentration in the room was reduced to 581 ppm, 477 ppm, and 438 ppm in the cases of 12 ACH, 24 ACH, and 48 ACH, respectively. As a result, the greater the number of air change per hour, the greater the performance for contaminant removal. It served as the foundation for assessing and optimizing the ventilation system of the portable negative pressure room.

Airflow and Pressure Design Review of Modular Negative Pressure Wards

“…Additionally, the ventilation performance of the negative-pressure isolation room was also verified depending on the operation of the exhaust fan in the attached toilet [6], and the extent of air pollution spread was investigated according to the negative-pressure control in the outpatient area of the hospital [7]. Previous studies have proposed design methods for AIIR ventilation systems and highlighted key considerations for both the design [8] and the operation [9] of HVAC systems. However, the scope of previous studies is limited to isolated patient rooms in conventional buildings, and few studies have evaluated airflow analysis and ventilation performance in modular buildings.…”

A CFD assessment on ventilation strategies in mitigating healthcare-associated infection in single patient ward

“…led to an increase in the velocity of the airflow in the room. Le, Nguyen and Kieu [13] suggested that changing the location of the exhaust air grilles could improve the ventilation performance in an airborne isolation room. Research also showed that human movement or sliding door motion could adversely impact the air velocity, pressure field and contaminant distribution, within general ventilated or specific negative pressure isolation rooms [14][15][16].…”

Numerical Computation of Hydrodynamic Characteristics of an Automated Hand-Washing System

“…Computational fluid dynamics (CFD) is known as an important technology for the study of the hydro-aerodynamic characteristics of fluid motion, and has been applied to a microchannel, sterilization chamber, torpedo-shaped underwater glider, centrifugal blower, an infection isolation room, etc. [7][8][9][10][11][12][13][14]. Le et al [7][8][9][10] investigated the thermocapillary migration of the fluid flows in a microchannel.…”