转轮复合式空调系统的数值计算及能耗分析

STUDIES ON NUMERICAL VALUE CALCULATION AND ENERGY CONSUMPTION OF DESICCANT HYBRID AIR CONDITION

主要研究了以太阳能作为再生热源的转轮除湿和蒸气压缩制冷相结合及转轮除湿、蒸气压缩和蒸发冷却相结合的2种复合式空调系统,同时对电能作为再生热源的上述空调系统进行研究,建立了系统的物理模型,并对系统性能参数进行数学描述。通过与相同条件下常规蒸气压缩空调系统的比较分析,得出复合式空调系统制冷剂质量流量分别减少50.20％和66.67％；压缩系统性能系数COP分别提高了26.49％和32.16％；压缩机能耗分别节省了62.64％和76.92％。电能作为再生热源时,总负荷能耗分别节省了32.68％和42.00％；当采用太阳能作为再生热源时,总负荷能耗节省更多的能量,分别为61.86％和71.16％(认为1kW电能等价于3kW热能)。研究还发现,室内相对湿度相同,随室内设计温度的提高,复合式系统压缩机能耗明显减少,节能率呈上升趋势；相反总负荷能耗的节能率呈下降趋势。干热气候条件下,系统节能较为明显：71.75％和85.96％(电能再生)。热湿气候条件下,系统节能不明显,甚至消耗更多能量,而采用太阳能时,复合式系统均具有明显节能效果。

Two solar desiccant hybrid systems were studied. One consists of a desiccant wheel, a sensible heat exchanger and vapor-compression unit. The other consists of a desiccant wheel, a sensible heat exchanger, vapor-compression unit and a direct evaporative cooler. We also study the two hybrid cycles with electricity as regeneration heat source. The physical model and mathematical model are established. It was found that, Compared with conventional vapor-compression air condition at the same operating condition, the refrigerant mass flow rate of hybrid air condition are reduced 50. 20% and 66.67% ; the COP value of vapor-compression subsystem are improved 26.49% and 32.16% ; the energy saving of vapor-compression subsystem are 62.64% and 76.92% ; the energy saving of the desiccant hybrid system are 32. 68% and 42.00% ; and the energy saving of the solar desiccant hybrid system are 61.86% and 71.16% （here we take lkW electric energy equal to 3kW heat energy）. The energy consumption of hybrid cycle at different indoor and outdoor air condition was also studied. We found that energy saving of vapor-compression subsystem increases with the increasing of indoor design temperature at the same indoor relative humidity, but reducing energy saving of hybrid cycle. The performance of the two hybrid cycles at four different climates was studied. The results showed that the hybrid cycles save more energy in hot, dry climate than it do in hot, humid climates. But the solar desiccant hybrid cycles always save more energy than a conventional vapor compressor cycle.