地源水分级供热系统构思与案例分析
System design and case study of graded heating by groundsource water
摘要：
为充分利用地源水冬季温度较高的特征以及室内热环境的非均匀性来提高能效，提出了地源水分级供热系统，即部分地源热量直接用于加热围护结构、减少室内直接散热量，部分地源热量则通过热泵提升品位后承担剩余部分负荷。选取北京一幢典型玻璃幕墙建筑，以地埋管地源热泵为例，构建了传热数值计算模型和能耗计算方法，分析了该系统在整个供暖季的逐时性能。结果表明：分级供热系统可以提高窗户平均温度2.3 ℃并降低16.8%的累计热负荷和33.1%的尖峰热负荷；由于地源水的直接利用无需机组能耗，该系统节能率达13.0%，初投资不变而运行费用有效降低。在室外温度较低时，负荷降低效果将更显著。此外，因该系统的末端应用于窗户，所以其适用于窗墙面积比较大的建筑。
Abstract：
To fully use the high temperature groundsource water and the nonuniform indoor thermal environment, proposes a graded heating system utilizing groundsource water. Part of the groundsource water is directly used to heat the building envelope while the other part is used by heat pump to deal with the residual heating load. Selects a building with typical glass curtain wall in Beijing, with groundsource heat pump as an example, constructs the heat transfer numerical calculation model and calculation method of energy consumption and analyses the hourly system performance in the whole heating season. The results show that the graded heating system can increase the window temperature about 2.3 ℃ and reduce 16.8% of the cumulative heating load and 33.1% of the peak heating load. The energysaving rate is as high as 13.0% because of the direct use of groundsource water without energy consumption. The initial cost will not be increased while the operation cost can be saved. The performance would be even better if the ambient temperature is lower.
Keywords:heating,lowtemperaturehotwater,groundsourceheatpump,heatingload,buildingenergyefficiency