| 摘要: |
| 本文针对空气源热泵热水器加热至较高水温时系统效率明显下降的问题，研究初始水温对系统性能的影响，通过实验改变初始水温，分析系统各参数随加热水温的变化规律，得到实际运行特性及制热性能恶化的原因。结果表明：相同初始水温，随着加热的进行，COP不断下降，加热前期下降趋势较为平缓，后期变大；不同初始水温，因系统开机时存在“预热”阶段，加热后期又受压缩机大量吸气带液的影响，故平均COP随初始水温的升高呈先减小后增大的趋势；少量吸气带液能有效降低排气温度，改善系统性能，大量吸气带液却增大系统功耗，加剧COP的下降趋势。此外，提出以排气温度下降后再次上升时的拐点作为压缩机开始大量吸气带液的参照点，从而提升系统性能。 |
| 关键词: 热泵热水器 初始水温 两相流 排气温度 |
| DOI： |
| 投稿时间：2017-03-23
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| 基金项目:上海市动力工程多相流动与传热重点实验室(1N-15-301-101)资助。 |
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| Effect of Initial Water Temperature on the Performance of Air-source Heat Pump Water Heater System |
| Yuan Zhaoyang,Tao Leren,Yu Zhongyang |
| (School of Energy and Power Engineering, University of Shanghai for Science and Technology) |
| Abstract: |
| When the air source heat pump water heater is heated to higher water temperature, the system efficiency will decrease obviously. In order to find out the reason of the decrease in heat efficiency and the operation rule of the system, this paper changes the initial water temperature, and studies the effect of temperature change on the parameters of the system. The results show that at the same initial water temperature, when the system operates, the COP has a slowly declining trend, which becomes violent later. With the different initial water temperature, because of the “preheating” stage and the affect by suction liquid of the compressor, the average COP decreases first and then increases with the uprise of the initial water temperature. In addition, a small amount of suction liquid can reduce exhaust temperature and improve system performance. But a large amount of suction liquid can increase the system power consumption, the decreased rate of COP will increase. This paper finally suggests that when the exhaust temperature drops again after the rise, the compressor begins to suction a large amount of liquid. |
| Key words: heat pump water heater initial water temperature gas-liquid flow exhaust temperature |
