0 引言
1 模型建立
Fig. 1 Diagram of trans-critical CO2 cycle heat pump system图1 跨临界CO2循环热泵系统简图 |
Fig. 2 Diagram of trans-critical CO2 cycle图2 跨临界CO2循环图 |
1.1 压缩机模型
1.2 换热器模型
1.3 膨胀阀模型
1.4 系统仿真平台
Table 1 Parameters of trans-critical CO2 air conditioning system表1 跨临界CO2空调系统参数 |
系统部件 | 参数 | 数值 |
---|---|---|
压缩机 | 排量/(cm3/r) | 8 |
转速/(r/min) | 2 000 ~ 8 800 | |
气冷器 | 尺寸/mm3 | 500 × 364 × 25 |
流程 | 10, 8, 6, 4 | |
空气迎风面积/mm2 | 137 200 | |
制冷剂对流换热面积/mm2 | 420 000 | |
蒸发器 | 尺寸/mm3 | 250 × 232 × 30 |
流程 | 8, 6, 6 | |
空气迎风面积/mm2 | 37 025 | |
制冷剂对流换热面积/mm2 | 300 000 |
Table 2 Simulation conditions of trans-critical CO2 air conditioning system表2 跨临界CO2空调系统仿真工况 |
工况 | 压缩机转速/(r/min) | 室外气冷器迎面风速/(m/s) | 室外气冷器进风温度/℃ | 蒸发器进风量/(m3/h) | 蒸发器进风温度/℃ |
---|---|---|---|---|---|
1 | 变量 | 5 | 35 | 700 | 25 |
2 | 3 000 | 变量 | 35 | 700 | 25 |
3 | 3 000 | 5 | 变量 | 700 | 25 |
4 | 3 000 | 5 | 35 | 变量 | 25 |
5 | 3 000 | 5 | 35 | 700 | 变量 |
2 㶲分析
3 㶲分析结果与讨论
3.1 压缩机转速的影响
Fig. 3 The effects of compressor speed on the exergy loss of system components图3 压缩机转速对系统各部件㶲损值的影响 |
Fig. 4 The effects of compressor speed on the relative exergy loss of system components图4 压缩机转速对系统各部件相对㶲损的影响 |
Table 3 Average relative exergy loss of system components at different compressor speeds表3 不同的压缩机转速下系统各部件平均相对㶲损 |
系统部件 | 平均相对㶲损/% |
---|---|
蒸发器 | 18.49 |
气冷器 | 26.93 |
压缩机 | 23.47 |
膨胀阀 | 31.10 |
Fig. 5 The effects of compressor speed on the exergy efficiency and total exergy loss of system图5 压缩机转速对㶲效率和总㶲损的影响 |
3.2 气体冷却器进风风速的影响
Fig. 6 The effects of air inlet speed of gas cooler on the exergy loss of system components图6 气冷器进风风速对系统各部件㶲损值的影响 |
Fig. 7 The effects of air inlet speed of gas cooler on the relative exergy loss of system components图7 气冷器进风风速对系统各部件相对㶲损的影响 |
Table 4 Average relative exergy loss of system components at different air inlet speed of gas cooler表4 不同的气冷器进风风速下系统各部件平均相对㶲损 |
系统部件 | 平均相对㶲损/% |
---|---|
蒸发器 | 17.42 |
气冷器 | 24.10 |
压缩机 | 20.10 |
膨胀阀 | 38.39 |
Fig. 8 The effects of air inlet speed of gas cooler on the exergy efficiency and total exergy loss of system图8 气冷器进风风速对总㶲损和㶲效率的影响 |
3.3 气体冷却器进风温度的影响
Fig. 9 The effects of air inlet temperature of gas cooler on the exergy loss of system components图9 气冷器进风温度对系统各部件㶲损值的影响 |
Fig. 10 The effects of air inlet temperature of gas cooler on the relative exergy loss of system components图10 气冷器进风温度对系统各部件相对㶲损的影响 |
Table 5 Average relative exergy loss of system components at different air inlet temperature of gas cooler表5 不同的气冷器进风温度下系统各部件平均相对㶲损 |
系统部件 | 平均相对㶲损/% |
---|---|
蒸发器 | 18.38 |
气冷器 | 22.56 |
压缩机 | 19.33 |
膨胀阀 | 39.73 |
Fig. 11 The effects of air inlet temperature of gas cooler on the exergy efficiency and total exergy loss of system图11 气冷器进风温度对总㶲损和㶲效率的影响 |
3.4 蒸发器进风量的影响
Fig. 12 The effects of air inlet volume of evaporator on the exergy loss of system components图12 蒸发器进风量对系统各部件㶲损值的影响 |
Fig. 13 The effects of air inlet volume of evaporator on the relative exergy loss of system components图13 蒸发器进风量对系统各部件相对㶲损的影响 |
Table 6 Average relative exergy loss of system components at different air inlet volume of evaporator表6 不同的蒸发器进风量下系统各部件平均相对㶲损 |
系统部件 | 平均相对㶲损/% |
---|---|
蒸发器 | 19.67 |
气冷器 | 23.93 |
压缩机 | 20.08 |
膨胀阀 | 36.33 |
Fig. 14 The effects of air inlet volume of evaporator on the exergy efficiency and total exergy loss of system图14 蒸发器进风量对总㶲损和㶲效率的影响 |
3.5 蒸发器进风温度的影响
Fig. 15 The effects of air inlet temperature of evaporator on the exergy loss of system components图15 蒸发器进风温度对系统各部件㶲损值的影响 |
Fig. 16 The effects of air inlet temperature of evaporator on the relative exergy loss of system components图16 蒸发器进风温度对系统各部件相对㶲损的影响 |
Table 7 Average relative exergy loss of system components at different air inlet temperature of evaporator表7 不同的蒸发器进风温度下系统各部件平均相对㶲损 |
系统部件 | 平均相对㶲损/% |
---|---|
蒸发器 | 20.04 |
气冷器 | 23.62 |
压缩机 | 19.34 |
膨胀阀 | 37.00 |
Fig. 17 The effects of air inlet temperature of evaporator on the exergy efficiency and total exergy loss of system图17 蒸发器进风温度对总㶲损和㶲效率的影响 |