摘要
采用温度频率法分析重庆气候得出可利用冷却塔免费供冷的主要时段集中在12月、1月和2月。根据冷却塔热工特性曲线,研究了出水温度随湿球温度变化规律并拟合了一系列对应水温差下二者变化的二次方程。然后以重庆某大型商业裙房作为研究对象进行了动态能耗模拟。结果表明,20%最大冷负荷可作为免费供冷工况下的典型负荷。由此计算得到免费供冷设计时,水温差为4℃,对应切换湿球温度为11.25℃较为合理。免费供冷系统可节约空调能耗20.1%。
Applicable period for tower cooling system is mainly concentrated in December, January and February based on Chongqing climate data analysis by BIN method. How supply water temperature varies with ambient wet-bulb tem- perature is studied on the basis of cooling tower thermal performance curve. And a series of quadratic fitting equations are obtained under different water temperature difference. Dynamic energy simulation is conducted for the selected commercial skirt building in Chongqing, which shows that 20% peak cooling load can be considered as typical load to be handled by the free cooling system. Furthermore, it is calculated out that design water temperature difference 4℃ with switched wet bulb temperature 11.25℃ is most reasonable according to experience formula of fan-coil under variable operating situation. Moreover, free cooling system can save energy consumption of air conditioning system by 20.1%.
