The CFD Analysis Of Respiratory Protective Mask And The Parameterized Modeling Study

Respiratory protective mask is an important protection equipment to prevent and control of occupational hazards, and respiratory protect workers' life safety in labor process. Wear a respiratory protective mask will generate additional respiratory resistance, which increase the work of breathing, influence the ventilation and reduce workers'work efficiency and ability. How to reduce the additional respiratory resistance is always the emphasis in international respiratory protection research field. This paper aims to build an airflow model in respiratory protective mask with computational fluid dynamics analysis and UG development tools, which is to analysis the influence of geometric structure of mask to respiratory resistance, in order to guide the re-design the respiratory protective mask.Computational fluid dynamics (CFD) is an effective computing technology to solve the complex flow and heat transfer problems in modern science. This paper analyses the breathing airflow inside the respiratory protective mask with CFD. The main contents as followed:make sure the characteristics of flow field in respiratory protective mask, the control equations for numerical simulation, the boundary conditions of the airflow and the three-dimension turbulent model according to the modern experiment technology and related aerodynamic research; build the geometry model of breathing airflow based on the 3D head model data which comes from human adaptation study, and meshed with professional grids software ICEM CFD; simulate analyze the meshed airflow model with computational fluid dynamics analysis software CFX to get the related breathing airflow parameters in certain geometrical structure of the respiratory protective mask.Parametric design, using a set of parameters to restrain the size relations of design object and expressing the geometric design object, is an effective means for preliminary design, product modeling, series design and dynamic design. This paper proposes the use of the method of parametric design the geometrical structure of the respiratory protective mask in order to make sure the geometrical parameters of the mask on the influence of respiratory resistance. With a simple kind of respiratory protection mask products, for example, this paper using UG development tools to create the parameterized geometrical model of the mask, including developing the model menus, the UG style dialogs and the modeling programs, and integrated in UG system. Thus realize the creating mode of the respiratory protective mask geometric model by geometric parameters.Combining with the computational fluid dynamics analysis technology and the parametric design, simulated the parametric geometric model in CFX and modified the geometric parameters by using the breathing airflow parameters from simulation, can realize the optimization design technology of respiratory protective mask, which improve the developing efficiency of respiratory protective mask product and reduce the development costs.