Research on the Model and Application of Airborne Virus Transmission in Cabin

Aiming at the virus spread in the cabin, the cabin environment was simulated. Using the combination of fluent and CFD in ANSYS, the environment in the cabin was simulated by researching the data, and the data was analyzed to determine the probability of droplets spreading within a certain range , Improve the construction of the air circulation system in the cabin, reduce the transmission probability of respiratory infections and viruses in the cabin. 1. Background With the spread of influenza and some pathogenic bacteria through civil airliners in recent years, the study of cross-transmission of pathogens in environments with poor air circulation and airtightness has become particularly important. Virus transmission in the cabin refers to harmful bacterial factors. The combination of chemical factors and air in the cabin has dangerous characteristics such as infectiousness and pathogenicity. This type of airborne bacteria spreads quickly and spreads widely. Compared with other confined spaces, the cabin is more unique, and its unique characteristics directly affect its probability of spreading germs. 2. Cogitation of the Research First, conducting in-depth understanding and analysis of virus attributes and transmission modes, and then understanding the environmental structure of different aircraft cabins. Taking a part of the cabin size as a reference by simulating part of the cabin environment to the virus transmission in the cabin. Setting some boundary conditions to simulate the air environment of the cabin. Assume that a patient is carrying the SARS virus and use existing data to simulate the environment in the cabin. Assuming the spread speed of virus droplets, use the modeling software CFD to establish a mesh model and the simulation software ANSYS to perform flow field analysis to calculate the spread of the infectious agents. Set the solution boundary to get the virus spreading in the cabin through the air Probability. Analyze the data to find the propagation probability of droplets in a certain range. After obtaining the relevant data, we will study the air circulation system in the cabin of the aircraft, and study how to build a more complete air circulation system in the cabin to reduce the probability of the spread of respiratory infections and viruses in the cabin. 3. Research Program 3.1 Analyzing aerosol transmission Aerosols are generally colloidal dispersion systems formed by solid or liquid small particles dispersed and suspended in a gaseous medium. The size can be in the range of 0.001 ~ 100 m m . The average person sneezes and coughs can emit 10,000 to 10,000,000 bacterial particles each time. The sizes of various viruses and bacteria in aerosols are very different. Respiratory infectious diseases are 2020 2nd International Symposium on the Frontiers of Biotechnology and Bioengineering (FBB 2020) Published by CSP © 2020 the Authors 261 affected by many factors through droplets and air transmission, such as the speed of droplets, the size of droplets, the number of droplets, the characteristics of droplets in different indoor environments, and the temperature and humidity of transmission. The bacteria studied in this paper is Serratia marcescens, the particle core diameter is 1 m m , particle density is 1000 3 / m Kg , and air density is 1.2 3 / m Kg . 3.2 Object of research The B737-800 was selected as the carrier for the case study of this subject. Its cockpit distribution, escape exits, seat arrangement and approximate model distribution are shown in Figure 1 below. Fig1. Boeing 737-800 cockpit map 3.3 Simulation Modeling Unigraphics (UG) NX9.0 modeling software was used to simulate a part of the cabin. The upper part of the model is regarded as a three-dimensional cabin model created by cutting the air-conditioning system, as shown in Fig. 2. The top view of the internal structure of the model is shown in Fig. 3. Fig 2 Front view of cabin model Fig 3 internal structure of the model In this research, the middle section of the cabin is selected for analysis and research. Each boundary port is named and the grid diagram shown in Figure 4 is divided. Fig 4 Front view of cabin model