高原地区空气源热泵及辅助热源复合系统能耗研究

高原地区空气源热泵系统供暖时应考虑设置辅助热源进行补充,常用的辅助热源包括太阳能集热器、电加热器、燃气锅炉供暖等。文章采用负荷频率法,对高原地区空气源热泵供暖系统,及采用不同辅助热源供暖的复合式系统等4种供暖方案的能耗和热源利用效率进行了对比研究,结果表明:采用空气源热泵+太阳能集热器供暖能耗明显小于其他方案,又充分利用可再生能源,为最优化运行方案;采用单纯空气源热泵机组供暖受到室外低温的影响,设备性能显著下降;采用空气源热泵+燃气锅炉供暖,节电但不节能,一次能源利用率较低,节能效益亦低;采用空气源热泵+电加热器供暖,二次能源利用率低,节能效益亦低。     

空气源相变储能复合热泵系统的运行分析

针对北方地区暖气片供暖不足、能耗高和不易除霜等问题,文章提出了一种空气源相变储能复合热泵系统,并选择典型日对系统进行实验,研究了系统的性能和稳定性。实验结果表明:空气源热泵与相变储能技术的耦合极大地提高了系统的运行效率;通过相变储能箱的温度调节,保障了二级热泵供热的稳定性,能够持续为末端用户提供60℃左右的热水;系统全天瞬时COP值稳定在2.6左右;在极端天气条件下,该系统能够进行储能除霜,减轻空气源热泵的压力。通过对比各种供暖方式的经济性和节能性发现,空气源相变储能复合热泵系统的经济性和环保性较好。     

增加蓄热装置的空气源热泵-太阳能互补供暖系统优化研究

针对低温工况下多能互补供暖系统的工作性能和经济性较差等问题,文章设计了太阳能-蓄热空气源热泵互补供暖系统,该系统在传统太阳能-空气源热泵互补供暖系统的基础上增加了蓄热装置,提高了空气源热泵入口的空气温度。文章基于TRNSYS软件构建了太阳能-蓄热空气源热泵互补供暖系统的仿真模型,并分析了空气源热泵制热能效比的变化,对比了入口处有、无蓄热装置时太阳能-蓄热空气源热泵互补供暖系统的热性能和经济性。分析结果表明:在增设蓄热装置后,空气源热泵的平均制热能效比提高了34.87%;在供暖期内,系统的平均代价火用效率提高了3.24%,总能耗减少了2×10~7kJ,费用年值与太阳能保证率之比ACSF减少了3.3元;系统中各部件的火用效率均有所提高,空气源热泵工作性能的改善最为显著,火用效率提高了4.63%。     

太阳能-空气源双能源复合供暖在严寒地区农村住宅中的应用研究

针对空气源热泵热风机在室外低温环境下供暖性能衰减，导致室内冬季供暖效果变差等问题，为充分发挥资源优势，提出了一种太阳能-空气源双能源复合高效集成装置，实现了太阳能集热器与低温空气源热泵热风机联合供暖。介绍了该集成装置的技术原理和控制策略，通过TRNSYS软件对该集成装置在哈尔滨地区农村住宅的供暖效果进行了研究，并对该集成装置供暖和低温空气源热泵热风机单独供暖的效果进行了对比分析。研究结果表明：太阳能-空气源双能源复合高效集成装置实现了太阳能与空气源两种能源更为合理的供暖时段匹配。在整个供暖季，与低温空气源热泵热风机单独供暖相比，该集成装置的供暖效果更好且能耗更低，其系统总能耗降低了2034.8 kWh，制热能效比提升了35.06%。     

寒冷地区户用大平板太阳能集热器-空气源热泵系统性能研究

针对太阳能难以单独稳定供暖和空气源热泵供暖成本高的问题，提出空气源热泵辅助太阳能稳定供暖构想，在甘肃省兰州市七里河区魏岭乡绿化村研发搭建大平板太阳能集热器-空气源热泵系统，对比研究晴天、多云和阴天3种典型工况下大平板太阳能集热器的集热效率、太阳能热泵和空气源热泵COP、太阳能保证率、系统总供热量和系统能效比等性能参数。结果表明：晴天、多云和阴天系统集热效率分别为44.9%、38.7%和20.6%,3种工况下太阳能热泵COP均为4.0，空气源热泵COP分别为3.5、3.3和3.1，太阳能保证率分别为38.1%、32.3%和12.9%，系统全天供热量分别为142.52、135.22和120.96 kWh，系统能效比分别为3.5、3.4和2.7。研究结果证明大平板太阳能集热器-空气源热泵系统用于寒冷地区单体建筑供暖的可行性，可为寒冷地区农村单体建筑的供暖提供一种新途径。     

北方农村中小学供暖方案选择

分析农村中小学供暖现状,提出几种适用于北方农村中小学的太阳能与辅助热源一体化供暖系统形式.以济南农村某小学为例,对太阳能与碳晶电热板复合供暖系统、太阳能与空气源热泵复合供暖系统、太阳能与地源热泵复合供暖系统及太阳能与沼气燃气锅炉复合供暖系统4种供暖方案的能耗、系统造价和系统运行费用进行研究.研究结果表明:对于该小学来说,太阳能与空气源热泵复合供暖系统长期运行较经济.     

太阳能与空气源热泵复合式供暖系统在西安地区的应用特性分析及评价

以西安地区的某个房间为研究对象,采用TRNSYS软件针对该房间分别应用太阳能集热系统、空气源热泵系统及太阳能与空气源热泵复合式供暖系统进行供暖时的情况进行了分析.首先,建立了太阳能与空气源热泵复合式供暖系统的仿真模型,并对其正确性进行了实验验证;其次,对比分析了在3种运行模式下各个系统的运行特性;最后,以系统能耗及能效...     

广东地区太阳能-空气源热泵复合系统供暖供生活热水实验研究

构建了一种太阳能-空气源热泵复合供热系统,在广东地区冬季的晴天和全阴天进行供暖供生活热水实验测试。针对办公建筑供暖供生活热水需求,定时间段供生活热水同时进行供暖实验。实验结果表明:晴天热泵相较于全阴天工况节电1.16 kW·h,供热效果优于全阴天工况,太阳能-空气源热泵复合供热性能相较于单独的空气源热泵更有显著优势;太阳能-空气源热泵复合系统供暖供生活热水期间,复合系统COP_(sys)平均值为4.71、波动范围在4.20～5.38,空气源热泵系统COP_(hp)平均值为4.60、波动范围在4.08～5.10。     

一种太阳能空气源/水源热泵系统的仿真分析

针对空气源热泵在低温环境下的低效问题与太阳能系统因依赖于天气状况而呈现的不稳定性等问题,提出了一种由太阳能水集热器、太阳能空气集热器、水源热泵和空气源热泵等4种装置组成的复合供暖、供热水系统,并根据日间与夜间的不同的气候条件,提出了5种运行模式。建立了系统的仿真模型,对系统在整个供暖季的运行仿真表明:该系统能够应对严寒天气并正常高效运转,在全供暖季的平均能效为4.21,各种工作模式的平均能效均在3以上,月平均能效为4~6。     

太阳能与土壤源耦合供暖系统的实验研究

在分析太阳能、土壤源热泵及联合供热特点的基础上,研究了太阳能热泵独立系统、土壤源耦合热泵系统运行模式的制热性能和节能效果,建立了太阳能蓄能-热泵耦合热泵系统的供暖模式及优化模型.通过采暖季初期的太阳能蓄能、供暖,土壤源热泵独立供暖及太阳能-土壤源耦合热泵供热的实验研究,验证了太阳能-土壤源耦合热泵供暖模式的可行性和经济...     

Investigation of thermal performance of a ground coupled heat pump system with a cylindrical energy storage tank

An analytical and computational model for a solar assisted heat pump heating system with an underground seasonal cylindrical storage tank is developed. The heating system consists of flat plate solar collectors, an underground cylindrical storage tank, a heat pump and a house to be heated during winter season. Analytical solution of transient field problem outside the storage tank is obtained by the application of complex finite Fourier transform and finite integral transform techniques. Three expressions for the heat pump, space heat requirement during the winter season and available solar energy are coupled with the solution of the transient temperature field problem. The analytical solution presented can be utilized to determine the annual variation of water temperature in the cylindrical store, transient earth temperature field surrounding the store and annual periodic performance of the heating system. A computer simulation program is developed to evaluate the annual periodic water and earth temperatures and system performance parameters based on the analytical solution. Copyright © 2003 John Wiley & Sons, Ltd.     

太阳能-空气复合热源热泵热水器的性能模拟与分析

介绍了一种新型太阳能—空气复合热源热泵热水装置(SAS-HPWH)。该装置通过使用独特设计的螺旋翅片蒸发管的平板型集热/蒸发器,可以在不同的天气情况下切换运行太阳能热源热泵模式、太阳能与空气双热源热泵模式和空气源热泵模式,制取生活热水。论文主要针对自行设计的一台150L的SAS-HPWH,建立系统的数学模型,并以太阳能输入比例为准则研究系统的运行模式与特性。模拟结果显示该热水器在不同天气特征情况下可高效率地制造55℃热水。论文还分析了太阳辐射、环境温度以及压缩机的容量对系统特性的影响,提出使用变频压缩机,根据不同的天气情况调节制冷剂流量,进一步提高系统的整体性能。     

Investigation of a combined solar–heat pump system for residential heating. Part 1: experimental results

In order to investigate the performance of the combined solar–heat pump system with energy storage in encapsulated phase change material (PCM) packings for residential heating in Trabzon, Turkey, an experimental set‐up was constructed. The experimental results were obtained from November to May during the heating season for two heating systems. These systems are a series of heat pump system, and a parallel heat pump system. The experimentally obtained results are used to calculate the heat pump coefficient of performance (COP), seasonal heating performance, the fraction of annual load meet by free energy, storage and collector efficiencies and total energy consumption of the systems during the heating season. Copyright © 1999 John Wiley & Sons, Ltd.     

建筑节能新方向:太阳能光伏-地源热泵系统

减少我国冬季采暖所造成的大气污染,降低供暖系统的能耗,节约能源一直是建筑节能追求的目标.目前太阳能光伏发电已经成为人类利用太阳能的最主要方式之一,地源热泵已被作为一项旨在解决建筑冷热源问题的新技术,日渐受到人们的重视.将光伏转换与热泵循环有机结合在一起,从而形成了太阳能光伏-地源热泵系统.该系统提高了光电转换和光热吸收效率,光电/光热综合利用,极大地提高了单位面积太阳辐照的利用效率,同时可提高热泵系统在寒冷地区运行的适用性;利用光电效应把太阳能中高能带区域的光能直接转化成电能,可大大提高太阳能的可用能效率;在增加能量储存装置和逆变器的条件下,可以使系统脱离公用电网运行,从而增加了系统的适用性和灵活性;与普通的空气源热泵相比,太阳能地源热泵具有较高的热性能,具有一机多用的功效;与建筑物相结合的太阳能热泵系统,可以增加建筑物的隔热效果,起到减少建筑物冷暖负荷的作用,同时可极大地减少环境污染.     

Latent heat storage for solar energy systems: Transient simulation of refrigerant storage

This paper presents a brief review of the available latent heat storage systems for solar energy utilization. A new concept of latent heat storage of solar energy via the refrigerant-absorbent mass storage in absorption cycle heat pump systems used for solar space heating/cooling has been proposed and assessed thermodynamically. A computer modelling and numerical simulation study shows that the concept of refrigerant storage is fundamentally sound, technically feasible and yields the following advantages over other storage methods: (i) the storage capacity per unit volume is high as the latent heat of vaporization of the refrigerant is high; (ii) the heat loss from the storage to the surroundings is minimum as the storage temperature is near the ambient; (iii) prolonged energy storage is possible with no degradation in system performance and hence suitable for combined solar heating and airconditioning. The effects of operating parameters on the energy storage concentration and storage efficiency have been studied in detail.     

Performance optimization and analysis of solar combi-system with carbon dioxide heat pump

In this paper, a solar combi-system which consists of solar collectors and a carbon dioxide heat pump is proposed and investigated through simulation and optimization. Performance analysis and comparison are primarily conducted to show the feasibility and reasonability of using a CO₂ heat pump as an auxiliary heater under local weather conditions. Then, a system model with a test building in TRNSYS is developed for performance optimization. The most influential variables are identified using influence and sensitivity analyzes of single parameters. Subsequently, a multi-parameter optimization using the high-weight parameters is carried out to obtain a final design result. The simulated results of the optimized case show that the average coefficient of performance of the CO₂ heat pump is 2.38, and the solar fraction of the system is 69.0% for the entire heating season. The time when a comfortable temperature level can be achieved in the indoor environment accounts for 81.6% of the entire heating season. Furthermore, the performance characteristics of the proposed system are evaluated in terms of the thermal balance, fraction of the thermal energy saving, feasibility of net zero energy, economic factor, and CO₂ emissions reduction.     

Thermal performance and pressure drop of rock beds with large storage materials

In air-based solar heating systems, the fan power needed to overcome friction loss in rock beds can reduce the benefit of the system. The system performance of rock beds with large-sized storage materials that have comparably low friction loss is studied. A theoretical model of the heat transfer process within the rock bed is developed for large storage materials. In this model, the temperature within the materials is assumed to be distributed quadratically and symmetrically at their center. The relationship between the model parameter and the air flow rate was derived from experimental measurements for some large materials as well as the pressure drop through the bed. The energy performance of heat pump solar systems with rock beds of various storage materials are studied by the computer simulation under Japanese winter weather conditions. It is concluded that the possibility exists for some large-sized storage materials to have almost the same performance as small-sized materials for heat pump solar systems.     

Experimental Analysis of a Solar Energy Storage Heat Pump System

This paper introduces a novel solar-assisted heat pump system with phase change energy storage and describes the methodology used to analyze the performance of the proposed system. A mathematical model was established for the key parts of the system including solar evaporator, condenser, phase change energy storage tank, and compressor. In parallel to the modelling work, an experimental set-up of the proposed solar energy storage heat pump system was developed. The experimental data showed that the designed system is capable of meeting cold day heating demands in rural areas of Yanbian city located in Jilin province of China. In day-time operation, the solar heat pump system stores excess energy in the energy storage tank for heating purposes. A desired indoor temperature was achieved; the average coefficient of performance of solar heat pump was identified as 4.5, and the system showed a stable performance throughout the day. In night-time operation, the energy stored in the storage tank was released through a liquid-solid change of phase in the employed phase-change material. In this way, the provision of continuous heat for ten hours was ensured within the building, and the desired indoor air conditions were achieved.     

基于太阳能集热-蓄热技术发展的吸收式制冷、供暖、供热水联供运行系统

基于太阳能集热器和热能蓄热器这一套能量转换和收集设备的基础上,为吸收式制冷、供暖、供热水提供热力驱动。系统组成包括太阳能集热蓄热部分,共用集热蓄热装置的制冷、供暖、供热水等三大功能循环系统,电路及其自动控制部分。该系统通过集热管和蓄热装置,将分散化、低品位的太阳能转换为较高品位的热能并存储起来,同时将其它形式的废热通过换热装置储存于蓄热装置内。三大循环能够按需获取热能,提高能源的利用效率。     

Simulation studies of the expected performance of Kerava solar village

The Kerava solar village is the first regional building complex in Finland with a combined solar heating and heat pump system using seasonal heat storage. The village will be completed at the beginning of 1983. In this study we describe the heating system of Kerava solar village. The heat demand was estimated by computer simulations. Different weather conditions and operational situations were considered. Under normal weather and operating conditions approximately 60 percent of the total heat demand of the Kerava solar village is estimated to be obtained from solar energy.