Numerical Simulation Of Different Kinds Of Air Distribution For The Indoor Environment Quality

The research of the air distribution is great important to the design of ventilating and air-conditioning engineering .Many researches show that the indoor air quality have close relation to the ventilation efficiency .Based these researches acquired and using a mathematical model ,this thesis tries to research the velocity field, temperature field, contaminant concentration distrtibutions of three-dimention indoor turbulent flow by means of computational fluid dynamics and heat transfer ,and then works out the ventilation efficiency. A better desired ventilation form is acquired by comparing the some efficiency values.On the basis of recently materials collected in the field at home and aborad ,this paper adoptsκ?εtwo-equation turbulence model by analysis and comparison, and sets up mathematical model to study velocity field, temperature field, contamination distribution, gives the boundary conditions, uses GAMBIT to build physical model and FLUENT for calculation.The ventilation of a typical chamber with a stable fixed pollutant emission is studied by founding different boundary conditions: two inlet-velocity 0.25m/s and 1m/s, three density 1.270kg/ m~3,1.500kg/ m~3and 1.000kg/ m~3, four air distributions the up-inlet and down-outlet on the same side ,the down-inlet and up-outlet on the same side, the up-inlet and down-outlet on opposite side and the down-inlet and up-outlet on opposite side. Using the program , velocity field, temperature field, contamination distribution are worked out .And get the ventilation efficiencies. After comparing energy saving, velocity field, temperature field and ventilation efficiency ,the up-inlet and down-outlet on the same side at inlet-velocity 0.25m/s when contamination density is heavier than air's or they are close is regarded as the better ventilation,and the down-inlet and up-outlet on the same side at inlet-velocity 0.25m/s when contamination density is much lighter than air's. At the end, assumes the experiment with"controlled dust"intrepidly to proof the results.