多热源驱动吸收式热泵系统性能研究

发布时间：2018-06-13 16:57

  本文选题：多热源 + 吸收式热泵　； 参考：《浙江大学》2014年博士论文

【摘要】：蒸气压缩式热泵系统需要消耗珍贵的电能,且常用制冷剂还会严重破坏臭氧层并产生全球变暖效应,以热能为驱动动力且使用环境友好型工质对的吸收式热泵系统可以极大缓解城市电力紧张和保护环境而受到人们的欢迎。传统的吸收式系统以及一些改进型的吸收式系统大都是由单一热源驱动,且对热源温度的要求也不同,很难同时利用低温太阳能热和地热以及工业生产中存在的大量动力余热。为此本文提出一种多热源驱动吸收式热泵系统,高低压发生器通过喷射器相互耦合,在能够以较简单结构高效利用动力余热的基础上,将传统单效吸收式系统无法利用的低品位太阳能热作为联合驱动热源。 开展了多热源驱动吸收式热泵循环的理论研究,分析发生压力对系统制冷/制热性能的影响,结果表明为了得到最优的性能,高压发生器发生压力和低压发生器发生压力以及喷射系数均需要优化,并分析了循环在变工况下的优化性能参数。制冷工况下,高压发生器发生压力在最优值正负偏离5K.Pa的范围内,循环COP都保持在0.9以上,说明该循环的可用性能较好。动力余热与太阳能负荷之比在3.5以上时,多热源驱动吸收式循环的COP都在0.9以上,较传统单效吸收式循环效率高20%左右,节能效果显著。 分析了输入相同动力余热与低温太阳能热负荷的条件下,采用多热源驱动吸收式循环所产生的制冷量/制热量远大于一套传统单效循环与一套传统两级循环所产生的制冷量/制热量和,采用多热源循环可以大大简化系统设备,大大减小了设备制造成本。 将整个循环看作由动力余热驱动子循环与太阳能驱动子循环组成,理论计算出太阳能负荷与动力余热负荷之比最大值,负荷比最大值随工况变化而变化。 设计并搭建了多热源驱动吸收式热泵系统实验台,实验研究了装置的制冷及制热性能,主要包括以高压发生器烟气入口温度、低压发生器Ⅱ太阳能热水入口温度、蒸发器冷媒水出口温度(制冷工况)、冷凝器空调热水出口温度(制热工况)为自变量,研究这些自变量与系统内部参数如：发生温度、蒸发温度、冷凝温度的变化关系,以及对系统制冷量／制热量和性能系数的影响。实验研究表明,系统制冷量/制热量理论模拟结果与实验结果符合较好。当烟气温度213℃时,系统提供6℃的冷媒水,制冷量可以达到12.5kW,制冷系数达到了0.78。系统提供43.5℃的空调末端热水,制热量可以达到26.6kW,制热系数超过了1.7,实现了低品位能源高效和充分利用,为多热源驱动吸收式热泵系统的设计以及规模化应用奠定了基础。
[Abstract]:Vapor compression heat pump systems consume valuable electrical energy, and common refrigerants can seriously damage the ozone layer and produce global warming effects. The absorption heat pump system, which is driven by heat energy and uses environment-friendly working pairs, can greatly alleviate the power shortage and protect the environment. The traditional absorption system and some improved absorption systems are driven by a single heat source, and the requirements of the heat source temperature are different. It is difficult to simultaneously utilize the low-temperature solar heat and geothermal energy, as well as a large amount of power waste heat in industrial production. In this paper, a multi-heat source driven absorption heat pump system is proposed, in which the high and low pressure generator is coupled with each other by ejector, and the power waste heat can be utilized efficiently with simple structure. The low-grade solar heat which can not be used in the traditional single-effect absorption system is used as the combined driving heat source. The theoretical study of absorption heat pump cycle driven by multi-heat source is carried out, and the influence of the pressure on the refrigeration / heating performance of the system is analyzed. The results show that in order to obtain the optimal performance, The generation pressure of high voltage generator and the pressure of low pressure generator as well as the injection coefficient need to be optimized, and the optimal performance parameters of the cycle under variable operating conditions are analyzed. Under the refrigeration condition, the cop of the cycle keeps above 0.9 in the range of positive or negative deviation of the optimal value from 5K.Pa, which indicates that the availability of the cycle is better. When the ratio of power waste heat to solar energy load is more than 3.5, the cop of absorption cycle driven by multiple heat sources is more than 0.9, which is about 20% higher than that of traditional single-effect absorption cycle. Under the condition of input the same power waste heat and low temperature solar heat load, The refrigerating capacity / heating capacity generated by using multi-heat source driven absorption cycle is much larger than that of one set of traditional single-effect cycle and one set of traditional two-stage cycle. The system equipment can be greatly simplified by using multi-heat source cycle. The equipment manufacturing cost is greatly reduced. The whole cycle is regarded as the maximum value of the ratio of the solar energy load to the power residual heat load, and the maximum value of the load ratio varies with the working condition. The experiment bench of multi-heat source driven absorption heat pump system is designed and built. The refrigeration and heating performance of the device is studied experimentally, including the inlet temperature of flue gas of high pressure generator and the inlet temperature of solar hot water of low pressure generator. The outlet temperature of refrigerant water in evaporator (refrigerating condition) and the outlet temperature of hot water in condenser air conditioning (heating condition) are independent variables. The relationship between these independent variables and internal parameters of the system such as occurrence temperature, evaporation temperature and condensation temperature is studied. And the influence on the cooling capacity / heating capacity and performance coefficient of the system. The experimental results show that the theoretical simulation results of the cooling capacity / heating capacity of the system are in good agreement with the experimental results. When the flue gas temperature is 213 鈩，

本文编号：2014718