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As people on the requirements to further improve the living environment, indoor and outdoor environmental quality are aroused great interest and attention, environmental evaluation methods have continued to increase. However, there is no respect of scholars indoor and outdoor as well as indoor climate similarity airflow in certain conditions, propagation characteristics of indoor air pollutants and evaluation studies, this paper as a background, the indoor temperature distribution aimed at in-depth study and stability and its relationship with indoor air pollutant dispersion and migration relationship. Introductory chapter summarizes the indoor environment evaluation method in recent years, a brief introduction to atmospheric stability, and stability analysis of indoor air research background, revealing the significance of this research. Paper, \ammonia and carbon dioxide in the stability of the different transmission characteristics, stability of the indoor air is conducted a preliminary classification, i.e. stable, unstable and neutral stability. In this paper, a comprehensive two-dimensional flow field to simulate the case of identical vertical jet boundary conditions case, case1 ~ case3, also established a three-dimensional model, using large eddy model to simulate the same case three different case. Research shows that the vertical jet, unstable to develop the horizontal turbulence, diffusion capacity enhancement of pollutants in the horizontal direction; stable inhibited its horizontal turbulence, pollutants easily spread in the horizontal direction; neutral stability is somewhere between the Room. The results also show that the vertical jet, γ> 0, with the γ increase its turbulence to develop, with the periphery of pollutant parameters easier mixing, diffusion capacity enhancement of pollutants in the horizontal direction, the performance levels of pollutant concentration levels gradient with γ decreases; γ <0, with the γ reduce its turbulence is suppressed, contaminants are more difficult to spread to the surrounding, the performance levels of pollutant concentration gradient with the decrease of γ. By comparing the level of the jet and two kinds of simulation results of vertical jets that: either the horizontal or vertical jet jets, γ> 0, the air in the room is both stability classification unstable, easier to lateral diffusion of pollutants, γ <0, the stability of the indoor air is stable in both categories, the lateral diffusion of pollutants difficult. In order to further establish and improve indoor air stability evaluation system, you also need to create a new model, the introduction of more comprehensive analysis of influencing factors, including the different airflow conditions, spatial shape factor, different obstacles (including moving objects) and other sources to study the dispersion of pollutants propagation strength characteristics, the establishment of a more reasonable stability classification of indoor air.
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