Discussion of Thermal Environment of Effective Utilization of Nature Source in Large Space Building

In transitional season, using mechanical ventilation can significantly reduce the air-conditioning energy consumption in large space building. In this paper, based on heat balance calculation, a nomograph about lowering switch point of a hall was drawn under different conditions such as different load factor, different outdoor and indoor temperature, and different ventilation rate. Under the load factor of 80%, switch points was 1.9□ and 17.9□, the minimum ventilation rate was 45% of design condition; Numerical simulation was carried out to calculate temperature and velocity filed, under small velocity case, the indoor thermal comfort was affected by load distribution, and the air flow organization of low-side wall return air was positive to good wind environment in occupant zone.