Numerical Simulation And Study On Air Distribution In The Atrium Of A Building

The modern atrium building is not only in large scale, but also modeledpeculiarly. It’s hard to meet various requirements for air conditioning design of thiskind of building according to the traditional experience. Therefore, computersimulation is necessary to predict the air distribution. In this paper, an open-styleatrium in Tianjin was chosen as the object and numerical calculation model had beenestablished. Numerical simulation of different designs in summer and winterconditions was performed by using CFD technology. Then analysis and evaluation ofsimulation results were given, which could provide a reference for the engineeringdesign in the future.Firstly, numerical simulation of air supply mode with lateral globe nozzle wasconducted based on both summer and winter conditions by utilizing Fluent software.The results show that the wind speed in the opposite of the lateral globe nozzledoesn’t meet the requirements for the thermal comfort as it’s too high. By adjustingthe air supply parameters, we can get the better air distribution and higher thermalcomfort. For the summer condition, the supply air velocity can range from2m/s to2.5m/s, the supply air temperature can range from17℃to18℃. For the wintercondition, the supply air velocity can be3.8m/s, the supply air temperature can be28℃, and the supply air outlet angle inclines to30°. However, the lateral globe nozzleis usually used on the condition that the supply air velocity is4m/s~8m/s, so it’s noteconomical and reasonable to use the lateral globe nozzle in the ‘Sunshine Paradise’atrium.Secondly, numerical simulation of air supply mode with lateral liner grillediffuseris was conducted based on both summer and winter conditions and the thermalenvironment at different supply air temperature, velocity and outlet angle wasanalysed and compared. The results reveal that for the summer condition, when thesupply air velocity is2m/s, the supply air temperature is19℃and the supply air outletangle is rised to20°~30°, the air distribution is uniformed. For the winter condition,when the supply air velocity is3.5m/s, the supply air temperature is28℃, and thesupply air outlet angle is inclined to45°, we can get the best air distribution andhighest thermal comfort. Thirdly, numerical simulation of floor-radiation heating combining outdoor airsystem under winter condition was performed. The results show that when using thisscheme, the average temperature in the activity area is about22℃, and the averagewind velocity is0.14m/s. At the same time, the PMV value is maintained between-0.3to0.3, and the PPD value is less than7%, which can meet the comfortrequirement of staff. Moreover, the energy consumption of floor-radiation heatingcombining outdoor air system and winter air conditioning system using the lateralliner grille diffuseris was calculated by using the eQUEST software. The results inferthat the floor-radiation heating combining outdoor air system has a significantenergy-saving effect in the winter condition, and the energy saving rate can reach to47%.Finally, experimental test in the atrium was conducted after the projectcompleted and the numerical simulation was proceded under the experimentalcondition. The comparison of the simulational and experimental data validates thefeasibility of CFD technology and the correctness of the model.