Numerical Simulation Of Airflow Distribution In Underground Building

As underground building is airproof and lack of sunlight, the indoor air has thecharacteristics of low temperature, large relative humidity and dirtiness. To meet therequirements of process, redundant humidity and heat in the air must be removed byreasonable airflow organizations.The underground building studied in this paper is mainly used in shipping maintenance.Because that its bottom is full of seawater, indoor relative humidity is large in damp season.However, it is hard to find the distributing rules of indoor thermal and moisture environmentbecause of the characteristics of underground building, coupled with the various factorsaffected indoor air.Based on the method of computational fluid dynamics, the velocity, temperature andrelative humidity fields of the different airflow organizations were simulated by using theFluent. The influence of different factors variation on airflow organization were investigated,including different airflow organization format, the position and shape of air inlet and outlet,and supply air parameters. The preliminary scheme of airflow organization was obtained.Using orthogonal experimental method, different schemes of airflow organization weresimulated. Analysis of range and variance were used for experimental results to find the keyfactors affect the airflow organization and to obtain excellent level. According to analysisresults and energy consumption of air conditioning, the optimized scheme of airfloworganization was obtained, which can satisfy the requirements of process and energyefficiency standards.Simulation results show that the most optimal scheme of airflow organization for theunderground building includes supply air from the middle, return air from the top and bottom,supply air temperature of45℃, horizontal distance of10m between air inlets, height of2mbetween the inlet and passage, and the shape of air inlet with the dimension of0.4m×0.1m.This paper provides a theoretical basis for the ventilation and dehumidification ofunderground building.