空调水系统变流量的运行特性

Energy-efficiency Performance with Variable Air-conditioning Water Flow Rate

为了降低空调能耗,探明空调水系统变流量工况下冷水机组性能参数和系统能耗的变化规律,对空调水系统变流量的运行特性进行了研究。利用DOE-2软件对某建筑模型进行了负荷预测,建立了适于变流量模拟的改进冷水机组和水泵模型,利用TRNSYS软件对空调系统在变流量运行工况下的系统总能耗、冷水机组能耗与COP值、水泵能耗和节能率进行了模拟和分析。结果表明,当冷冻水或冷却水流量分别从100%降至50%时,冷水机组COP值分别降低了8.04%和9.96%;而系统总能耗相对定流量系统而言,分别降低了15.79%和13.56%。这表明,无论是冷却水变流量还是冷冻水变流量均降低了冷水机组的COP值,但同时也能降低系统总能耗;采用冷冻水变流量技术比冷却水变流量的节能率高,冷却水变流量范围不宜过大。

For reduce energy consumption and improve operating efficiency of air-conditioning, the influence of variable flow rate of chilled water and cooling water on the chilled COP and the energy consumption was analyszed. The maximum cooling load was predicted by DOE-2 software and built the chiller and pump models for simulate. The chiller COP and energy consumption of chiller and pump were computed utilizing TRNSYS. Result showed the chiller COP have decrease 8.04% and 9.96% when the chilled water and cooling water flow rate from 100% to 50%, while the total energy consumption has reduced 15.79% and 13. 56% relatively fixed flow rate system. This shows that both the cooling water flow or variable flow chilled water chillers are reducing the value of the COP, but it also can reduce overall system energy consumption; the technology of variable chilled water flow rate will more high-efficiency than variable cooling water flow rate and the scope of variable cooling water flow should not be too large.