低温热源驱动溴化锂第二类吸收式热泵的实验研究

根据溴化锂第二类吸收式热泵系统的传热、传质平衡以及各部件的传热关系,建立了系统的稳态数学模型.利用模拟计算得出了相应的设计参数,建它了热负荷为小型LiBr-H2O第二类吸收式热泵系统实验台,对废热驱动的实验系统在不同运行工况下进行了实验研究.分析了系统主要运行参数各换热设备的进口水温和质量流量对系统性能的影响趋势和规律.     

直膨式太阳能热泵采暖蓄能制冷应用研究

以U型管式太阳集热器作为热泵系统的蒸发器,利用太阳能工程及传热学等热力学相关知识,对该直膨式太阳能热泵系统进行能效分析。论证结果表明:太阳集热器的综合效率达到90%以上,系统能效COP约3.53,同时以上海地区单户采暖为例,描述直膨式太阳能热泵采暖蓄能供冷系统的设计过程,该研究能够为太阳能热泵采暖及蓄能供冷的优化设计提供借鉴。     

真空管直膨式太阳能热泵系统性能分析

该文将真空管集热器与直膨式太阳能热泵结合,提出一种真空管直膨式太阳能热泵系统。实验研究典型工况下太阳辐照度、循环水温度对系统性能的影响,并探讨压缩机变频条件下系统的动态性能。结果表明,提高太阳辐照度、降低循环水温度有利于提高系统性能,在太阳辐照度为850 W/m2,循环水温度为55℃时系统取得最大COP,为5.36。压缩机频率为42 Hz的系统COP为4.08,较45、47、50 Hz分别提高1.23%、8.5%、13.6%。     

第二类LiBr-H2O吸收式热泵热力循环分析

本文对以LiBr-H2O为工质对的第二类吸收式热泵即吸收式热变换器（absorption heat trans-former）的热力循环过程进行了模拟计算。详尽分析研究了循环倍率、稀溶液的浓度、蒸发温度、冷凝温度对系统的性能系数COP、发生温度、吸收温度、工业余热提升温度的影响规律。模拟计算的结果与作者研制开发的工业规模第二类吸收式热泵系统的性能测试数据进行了对比，结果表明，理论模拟计算的结果同实测的数据吻合较好。所得到的规律性将为这类吸收泵性能的提高、系统的优化设计与工业开发提供了必要的理论依据。     

间接膨胀式太阳能高温热泵系统运行性能实验研究

为研究间接膨胀式太阳能高温热泵系统实际应用的可行性和有效性,搭建实验平台,在天津地区气象条件下对高温热泵全天动态运行特性开展实验研究,分析太阳辐射强度、水箱储热性能、冷凝温度及膨胀阀开度对系统运行性能影响。结果表明:平均太阳辐射强度由396 W/m2增加到563 W/m2,高温热泵性能系数COP由3.62增至3.93;因水箱储热功能,间接膨胀式系统在太阳辐射强度剧烈波动时能够保持高温热泵相对稳定的蒸发温度;当蒸发温度固定时高温热泵COP随冷凝温度升高而降低,冷凝温度由70 ℃增至80 ℃,COP由4.32降至2.76;膨胀阀开度由150步增至250步,高温热泵全天平均COP由3.14升至5.12,排气压力降低46%。     

太阳能吸收式制冷空调集热器的研究

介绍了用于太阳能吸收式制冷空调的各种集热器,根据它们的应用情况分析了太阳能吸收式制冷空调的发展趋势及对集热器的要求,并提出了CPC热管式真空管集热装置,对其进行了研究和展望.     

高温热泵在木材加工行业中的应用

分析了国内外木材加工行业中高温热泵的研究与应用现状,提出了采用高温热泵回收单板干燥尾气的方案,认为当前要重视高温热泵工质及相应热泵系统的研制,发展高温热泵与太阳能和常规蒸汽干燥的联合干燥技术,使高温热泵干燥装置标准化和规范化,保证机械的产品质量与稳定性,扩大高温热泵干燥机在我国的使用范围。     

太阳能吸收式与吸附式制冷技术的比较与发展

通过对太阳能吸收式和吸附式制冷的工作原理、制冷工质对、结构和多效/多床系统的综合分析比较,对提高以上2种系统COP的方法及将来的发展趋势进行了阐述。结果表明:除了使用混合溶液为工质对和聚合集热器之外,运用多效和多床系统也可以很好地提升其制冷的效率。     

R290直膨式太阳能热泵供暖系统实验研究

为分析直膨式太阳能热泵耦合地板辐射供暖系统在北方寒冷地区的实际运行特性,设计并搭建以丙烷(R290)为工质的直膨式太阳能热泵供暖实验平台,分析冬季不同运行工况下环境参数对系统热力性能的影响。实验结果表明：系统可实现室内供暖的稳定性,实验测试期间平均室温保持在16.1～20.8℃之间,热泵系统性能系数(COP)保持在2.57～4.30之间,供暖系统COP保持在2.24～3.98之间。太阳辐照度每增加50 W/m²,热泵系统COP提升4.9%;环境温度每升高1℃,热泵系统COP提升2.4%。太阳辐照度对热泵系统的电子膨胀阀开度和工质质量流量影响较为显著。当终止水温从45℃提升至55℃时,热泵系统COP降低12.2%;而在终止水温为50℃时,供暖系统COP达到最大值3.37。     

水循环式热泵干燥装置的分析

热泵干燥装置具有节约能源、环境友好、可低温干燥等特点。水循环式热泵干燥装置是指热泵和干燥部分通过水循环耦合而成的热泵干燥装置,与热泵和干燥部分直接耦合相比,具有不向环境排放热量、机组调控性好、对干燥过程的匹配性好、成本低等优势,是一种较适宜于中小型热泵干燥装置的结构型式。     

太阳能制冷与供暖系统的设计与比较

根据上海的气候条件，以上海地区某写字楼为对象，提出4种太阳能驱动的溴化锂吸收式与电动蒸汽压缩式热泵联合制冷与供暖系统。这4种系统分别由热管式真空管集热器或抛物面槽形聚光集热器，单效或双效溴化锂吸收式制冷机，以及风冷热泵或水源热泵构成。分析比较这4种系统的节能型和经济性的结果表明，采用抛物面槽形聚光集热器＋双效溴化锂吸收式制冷机＋风冷热泵组成的系统，同时具备较好的节能性与经济性，一次能源利用率可降低约50％。     

太阳能-空气源热泵联合干燥系统设计及干燥枸杞的实验研究

为缩短枸杞干燥时间,提高干制枸杞的质量,减少能源消耗,本文提出了一种新型太阳能–空气源热泵联合干燥系统。该系统主要由太阳能集热器和空气源热泵机组等设备组成,可以实现太阳能单独干燥、热泵单独干燥和太阳能–空气源热泵联合干燥三种工作模式。本文根据枸杞的干燥特性,分段设定最佳的干燥温度,进行了热泵单独运行和太阳能–热泵联合运行两种工作模式下干燥枸杞的对比实验。结果表明,干燥50 kg枸杞,太阳能–热泵联合运行比热泵单独运行节省了2.9 kW?h电能,若同时除去系统本身的耗能,节省的电能占热泵单独运行耗电量的29.5%。同时,与太阳能单独干燥相比,太阳能–热泵联合干燥具有较高的除湿能耗比,两者最大差值为0.71 kg/(kW?h)。本文提出的太阳能–热泵联合干燥系统具有提高干燥产品的品质、缩短干燥时间和节约干燥成本等优点,适宜推广。     

太阳能-热泵联合干燥木材的实验研究

介绍了太阳能.热泵联合干燥的目的、意义、设备组成与工作原理,列出了联合干燥设备的主要参数与性能测试数据。绘出了太阳能干燥与联合干燥的工艺曲线。将太阳能-热泵联合干燥与常规蒸汽干燥(又称热风干燥)进行了经济分析对比,联合干燥的节能率在70%左右。     

Thermal performance of a solar-assisted heat pump drying system with thermal energy storage tank and heat recovery unit

Thermal performance parameters for a solar-assisted heat pump (SAHP) drying system with underground thermal energy storage (TES) tank and heat recovery unit (HRU) are investigated in this study. The SAHP drying system is made up of a drying unit, a heat pump, flat plate solar collectors, an underground TES tank, and HRU. An analytical model is developed to obtain the performance parameters of the drying system by using the solution of heat transfer problem around the TES tank and energy expressions for other components of the drying system. These parameters are coefficient of performances for the heat pump (COP) and system (COPs), specific moisture evaporation rate (SMER), temperature of water in the TES tank, and energy fractions for energy charging and extraction from the system. A MATLAB program has been prepared using the expressions for the drying system. The obtained results for COP, COPs, and SMER are 5.55, 5.28, and 9.25, respectively, by using wheat mass flow rate of 100 kg h⁻¹, Carnot efficiency of 40%, collector area of 100 m², and TES tank volume of 300 m³ when the system attains periodic operation duration in fifth year onwards for 10 years of operation. Annual energy saving is 21.4% in comparison with the same system without using HRU for the same input data.     

太阳能热泵系统的试验研究与分析

为研究以太阳能为低温热源的供热运行特点,建立了太阳能热泵系统试验台及试验台测量系统,使用数据分析软件处理不同工况下的试验数据,分析了蒸发和冷凝温度对吸热量、制热量、压缩机状态、系统COP的影响。结果表明,太阳能热泵系统在运行期间节能效果明显,蒸发温度的增大有利于提高太阳能热泵系统的工作性能。     

太阳能与热泵联合干燥木材的优化匹配

介绍了太阳能与热泵联合干燥系统的组成与工作原理.通过理论分析与实验研究探讨了太阳能与热泵联合运行的优化匹配,当太阳能供热量能满足木材干燥所需热量时,由太阳能系统供热;否则由太阳能与热采联合供热;阴雨天和夜间由热泵供热.当太阳能送风温度低,但高于环境温度时,低温太阳能向热泵送风,可以提高热泵的供热系数和供热量.对应于一定的环境温度,太阳能向热泵送风有一个相匹配的最低温差.例如当环境温度为24℃时,通过理论和实验求得太阳能向热泵送风与环境温度间的最低送风温差分别为4℃和6℃.     

APPLICATION OF HEAT PUMP SYSTEMS FOR ENERGY CONSERVATION IN PAPER DRYING

Drying is one of the most energy intensive and common operations in the chemical and process industries. Scope for energy recovery is substantial, particularly from the latent heat of the exhaust moist air. Using real operating data from a major Swedish mill, optimal energy conservation strategies were investigated using different heat pump systems in paper drying. Simulation results are compared for compressor-driven and absorption heat pump systems. An absorption heat transformer was also investigated. A CH₃OH–LiBr double-lift cycle would have a low COP value due to the low temperature of the moist air stream and the restricted temperature of the cooling water available. A total of 30 MW thermal equivalent is currently needed in the mill at a temperature of 75°C for mixing-pits, district heating and a log store. Exhaust humid air at a temperature of 54°C from only three of the paper machines was used in this study. SHPUMP simulations revealed that installing a mechanical heat pump unit using HFC 134a would result in a recovery of 22 MW due to the temperature level of this application. On the other hand, 12 MW can be recovered with an absorption heat pump. To optimize the operating conditions, H₂O–NaOH was selected as the best of three based on exergy index criteria. Assuming a steam cost of 22 $/MW h and an electricity cost of 32 $/MW h, the pay-off periods would be 3·3 and 2·9 years for compressor-driven and absorption heat pump alternatives, respectively. © 1997 by John Wiley & Sons, Ltd.     

冰源热泵系统在设施水产养殖中的技术经济性研究

针对目前刺参养殖的水温调控系统能耗大及适用性差等问题,提出基于冰源热泵的高效清洁供热及结合跨季节蓄冷实现全年冷热管理的技术思路,采用冰源热泵系统和跨季节蓄冷型冰源热泵系统对养殖水体温度进行调控,建立模型定量对比分析系统的运行能效及技术经济性。结果表明:（1）冰源热泵系统供热和供冷时的性能系数分别为3.33和3.39,全年一次能源利用率为1.05,比燃煤锅炉+冷水机组系统高出34.6%;费用年值最低,投资回收期为3 ~ 5年,具有良好的经济效益和应用前景。（2）跨季节蓄冷型冰源热泵系统全年一次能源利用率为1.46,比冰源热泵系统高39.1%,全年运行费用最低;跨季节蓄冷技术的应用有效提升了系统能效,大幅减少供冷运行费用,具有较大发展潜力。     

A solar assisted heat pump drying system for grain in-store drying

For grain in-store drying, a solar assisted drying process has been developed, which consists of a set including a solar-assisted heat pump, a ventilation system, a grain stirrer, etc. In this way, low power consumption, short cycle time and water content uniformity can be achieved in comparison with the conventional method. A solar-assisted heat pump drying system has been designed and manufactured for a practical granary, and the energy consumption performance of the unit is analyzed. The analysis result shows that the solar fraction of the unit is higher than 20%, the coefficient of performance about system (COP_S) is 5.19, and the specific moisture extraction rate (SMER) can reach 3.05 kg/kWh.     

Review of solar assisted heat pump drying systems for agricultural and marine products

Combining solar energy and heat pump technology is a very attractive concept. It is able to eliminate some difficulties and disadvantages of using solar dryer systems or solely using heat pump drying separately. Solar assisted heat pump drying systems have been studied and applied since the last decades in order to increase the quality of products where low temperature and well-controlled drying conditions are needed. This paper reviewed studies on the advances in solar heat pump drying systems. Results and observation from the studies of solar assisted heat pump dryer systems indicated that for heat sensitive materials; improved quality control, reduced energy consumption, high coefficient of performance and high thermal efficiency of the dryer were achieved. The way forward and future directions in R&D in this field are further research regarding theoretical and experimental analysis as well as for the replacement of conventional solar dryer or heat pump dryer with solar assisted heat pump drying systems and solar assisted chemical and ground source heat pump dryers which should present energy efficient applications of the technologies.