城市局地气温对建筑冷负荷的影响

The Impact of Local Air Temperature on Building Cooling Load

局地气候区(Local Climate Zone,LCZ)是一套用于城市气温研究的客观、标准、通用的局地热气候分类方法。对南京9个不同类型LCZ地块的近地气温进行实测(2016年07月22日至2016年09月30日),然后结合EnergyPlus软件分析局地气温对典型居住建筑和办公建筑冷负荷的影响。结果表明:1)热岛强度夜间显著高于白天;对于整个研究时段的夜间平均热岛强度,紧凑建筑区最高(1.8～1.9℃),其次是开敞中高层建筑区和重工业区(1.4～1.5℃),低层建筑区为0.9～1.1℃;稀疏建筑区最低(0.3℃);热岛强度在少云弱风的典型天气条件下更高;2)与采用郊区气象参数的基准案例相比,整个研究时段各LCZ地块居住建筑的累积冷负荷增幅为8%～17%,办公建筑的累积冷负荷增幅为4%～7%;典型天气条件下的夜间时段各LCZ地块的居住建筑累计冷负荷增幅为8%～26%。

The Local Climate Zone (LCZ)scheme aims to provide an objective and standardized classification protocol for urban temperature studies in most cities.The field air temperature and humidity data was collected from the 9 LCZ sites in Nanjing city from July 22 to September 30,2016.The software EnergyPlus was employed to simulate the impact of local thermal climate on the cooling loads of the apartment and office buildings.The results show that :1)the heat island intensity during the nighttime is significantly higher than that during the daytime ;the tendency of the average nocturnal UHI magnitudes for the whole study period is clear -the LCZ classes with compact buildings record the highest values (1.8-1.9℃ ),while the LCZ classes with open buildings range from 0.9℃ to 1.5℃,and the sparsely built zone the lowest (0.3℃ );the UHI intensity appears to be higher under the ‘ideal'conditions of cloudless skies and weak winds;and 2)for the studied LCZ sites,the accumulated cooling loads increased by 8%-17% for the apartment building and by 4%-7% for the office building (4%-7%),compared to the reference case using the meteorological data from the rural weather station;for the nighttime of the typical weather conditions,the accumulated cooling loads of the apartment building for the LCZ classes increased by 8%-26%.