Large Space Building Different Form Of Opening On Indoor Thermal Environment Research

To better meet the requirements such as ventilation, daylighting etc, there are upper-openings in large space buildings. It was found that upper-opening had a essential infection on indoor thermal environment and energy-consumption of large space. And different form of upper opening has different influence on indoor thermal environment and energy-consumption. This paper investigates the indoor thermal environment and the energy-consumption in large space building of stratified air-conditioning with upper-side opening and roof opening using CFD technique, theoretical analysis and site-measurement.This paper highlights the factors that should be considered when applying computational fluid dynamics (CFD) to large space design, and gives practical recommendations on how to achieve accurate results. Wall temperature is acted as the first kind boundary condition of CFD. Considering the effect of surface-to-surface radiation exchange, surface-to-surface radiation modeling is incorporated into CFD simulation using GEBHART absorbing coefficient. Further, mathematical modeling is established to calculate the convection coefficient that is a key factor of surface-to-surface heat exchange for more accurate prediction of CFD. The paper also compares CFD results with site-measurement data. Therefore, CFD results agree well with the data and the average difference between CFD results and the site-measurement data is 6.9%.The temperature and velocity field of large space are simulated by PHOENICS software. And indoor cooling load is calculated by three methods: cooling load calculation of stratified air-conditioning, numerical simulation and site-measurement data. CFD calculation and stratified air-conditioning calculation of cooling load show good agreement with site-measurement data. The differences of indoor air environment and energy consumption corresponding to two kinds of openings are discussed. It can be found that indoor cooling load in the case of upper-side opening is larger than that in the case of roof opening. The influences of the structural parameters and air-conditioning running parameters on indoor thermal environment and energy consumption are also presented in this paper. In the case of roof opening, indoor cooling load increases with the increase of the nozzle height. When outdoor air velocity is close to 3ms-1, an...