Numerical Simulation Research Of Several Problems In Man Machine And Enviroment Engineering

To solve several main problems of Man Machine and Enviroment Engineering(MMEE), the numerical simulation method of MMEE is researched and applied in this dissertation. At present, these problems can not be sovled by experimental way in China. So, the study work of this dissertation has important theory significance and engineering merit.The dissertation includes six chapters. In the first chapter, the history and state of art of studies on the numerical simulation method of MMEE are introduced, and the numerical simlution method of turbulent flow and heat transfer is reviewed. In the second chapter, based on the analysis of the numerical simlution method of turbulent flow and heat transfer in the complex geometrical domain, the grid generation technique, difference scheme of convective and diffusive terms, pressure and velocity correction methods, turbulent models and arithmetic of nonlinear equations, which are suitable for the numerical simlution of MMEE, are determined. In order to investigate the static and dynamic characteristics of the exhalation valve plate in pressure oxygen mask, the numerical simulation method of the exhalation valve plate's static and dynamic characteristics is presented in the third chapter. By the comparison of the static simlation and experimental results, the effectiveness of the proposed numerical simulation method of the static characteristic is verified. To realize the numerical simulation of the dynamic characteristic, the dynamics equation of the exhalation valve plate and control equation of flowfield are coupling solved with numerical simulation method. Based on the proposed simulation method, the dynamic charateristic of exhalation valve plate can be analized and the cause of dithering of the valve plate can be found out. In the forth chapter, the Reynolds averaged Navier-Stokes equations and Low Reynolds number k-e model are used to simulate the airflow within the cabin. In order to obtain a higher accurate result, the convection terms of equations is treated by MUSCL scheme. The two-dimensional and three-dimensionalmodel are used to simulate the air distribution within the cabin, which is affected by buoyancy and the inlet nozzle configuration and velocity of air. In the fifth chapter, the Eulerian model for airflow containing water droplets is proposed by using multifiuld model, as an alternation to the Lagrangian. The impingement limits and collection coefficient coefficiencies, which are affected by the changes of the MVD(Mean Volume Diameter) and AOA(Angle Of Attack), are computated. The moving boundary techolique is proposed to simulate the ice accretion. In the last chapter, the research work in this dissertation is generalized.