太阳能辅助多功能热泵.doc

太阳能多功能热泵实验研究
大摘要
本文提出一种将家用热泵热水器和太阳能热水器相结合，经改造后构成的可以实现多种功能的太阳能辅助多功能热泵系统，该系统在实现了夏季制冷、冬季空气源热泵制热、全年热泵制取热水以及太阳能制取热水四种功能的基础上，增加了有两级冷凝的夏季制冷兼制热水和冬季太阳能热水辅助水源热泵制热功能，实现了废热的回收利用，减少了室外热污染，同时缓减了冬季空气源热泵制热时室外机结霜的问题。
本文详细介绍了所提出的系统运行原理以及各个功能模式的实现，按照所设计原理图的制冷剂循环管路，组装了实验样机，对夏季制冷、制冷兼制热水、冬季空气源热泵制热、太阳能热水辅助水源热泵制热以及全年热泵制取热水五种运行模式进行了实验研究，并对系统的运行性能给予了详细分析，结果表明，系统各模式在相应的实验条件下均有较好的运行效果，所得主要结论如下：
1．夏季室内单制冷实验过程中，系统的吸气温度维持在10.0℃，排气温度维持在79.0℃，实验过程中，工作状态平稳，平均制冷量为3803W，制冷平均COP值约为3.1；
2．对夏季制冷兼制热水模式进行详细的实验研究，结果表明，在室外风机未开启时，系统的制热水速度较快，而制冷量平均值为2900W；在风机开启以后，系统制冷量迅速提升，最大值达到3700W，平均值为3500W，制冷平均COP值为3.0，而蓄热水箱内热水温升很缓慢，热水从45℃加热至55℃，用时280min。整个运行过程中，系统综合COP值在室外风机未开启时在5.0以上，风机开启后仍高于3.0；
3．冬季空气源热泵制热时，系统运行稳定，较高的排气温度使得系统有更多的热量可以释放给室内，满足室内热负荷，其平均制热量为3750W，实验期间，系统的平均制热COP值为3.4；
4．太阳能辅助水源热泵供热时，当水源温度在30℃~40℃之间时，系统的制热COP值大于4.0，高于空气源热泵制热，随着蓄热水箱内热水温度的下降，系统的COP值虽然仍高于空气源热泵制热，有一定优势，但是由于压缩机排气温度的下降，导致系统制热效果有所下降；
5．对太阳能辅助多功能热泵制热水性能分析表明：随着环境温度的升高，系统吸、排气压力均有所升高，在较高的环境温度下，系统仍在安全范围内工作；系统制热水性能受环境温度的变化影响较大，环境温度为19.4℃时，制热水时间明显缩短，性能系数COP也有较大提高，制热水时间比6.7℃时缩短了58min。
文章的最后针对实验过程中出现的制冷剂不足和吸气过热度太大的现象，进行分析后，在原有的系统原理图基础上，提出了改进方案，增加了两个电磁阀和一段毛细节流管，用来解决系统可腀@鱿值纳鲜鱿窒螅徊⒍韵募局评浼嬷迫人投咎裟芨ㄖ缺弥迫攘街中略龉δ艿目刂品椒ń辛私樯堋�

关键词 太阳能；多功能热泵；两级冷凝；性能系数





















Abstract
In this paper, a solar assisted multi-functional heat pump is proposed based on a detailed solar heat pump survey, which has integrated household heat pump air conditioner with solar hot water heater. On the basic functions of retaining the original summer cooling, air source heat pump heating in winter, heat pump water heater throughout the year and solar hot water heating modes, it has added summer cooling integrated water heater and solar hot water auxiliary water source heat pump heating function in winter. The new functions has achieved recycling of waste heat, reduced thermal pollution, and mitigated the problem of outdoor coil frost in air source heat pump mode.
This paper describes the operating principle and the realization of each mode of the proposed system. The experimental prototype has been established in accordance with the schematic design of the refrigerant circulation. The paper studied five operation modes like summer cooling, cooling and water heating, air source heat pump system in winter, solar hot water assisted water source heat pump and heat pump water heater around the year. Furthermore, it has provided a detailed analysis of the operation performance. The results show that the system performs well under the corresponding experimental conditions. Here are the main conclusions obtained:
1. During the summer cooling experiment, when the compressor's suction temperature is 10.0℃ and exhaust temperature is 79.0℃, the system has a smooth working state with the average cooling capacity is 3803w and the average COP is 3.1;
2. A detailed summer cooling integrated water heating mode experimental study has been carried out. Its results show that when the outdoor fan is turned off, the water heating rate is faster and the average cooling capacity is 2900w; after the fan is turned on, the system cooling capacity increases rapidly to the maximum value 3700w, the average cooling capacity is 3500w, and the average cooling COP is 3.0, while the heat storage tank water temperature increases very slowly, the hot water temperature changes from 45℃ to 55℃ within 280 min. During the whole operation process, when the outdoor fan is turned off, the integrated system COP value is over 5.0; after the fan is turned on, the value is still higher than 3.0;
3. The system operates stably during the air source heat pump heating mode. With the high exhaust temperature, the system can release more heat to the room to meet the indoor heat load, whose the average heat capacity is 3750w, and during the experimental period, the system′s average heating COP value is 3.4;
4. The te..