空气源单、双级燃气机热泵的应用及其效益分析

提出一种单、双级空气源燃气机热泵,并从多个角度上同传统的蒸汽压缩式热泵和单级燃气机热泵作了比较。结果表明,这种热泵在一次能源利用率、火用效率和经济性上有较大优势,它的推广使用将扩大热泵的适用范围和使用时间,尤其在三北地区。     

太阳能、热泵辅助燃气供热系统实验研究

搭建了太阳能、热泵辅助燃气的供热系统测试平台,对太阳能辅助燃气供热系统、热泵辅助燃气供热系统以及太阳能、热泵辅助燃气供热系统的热性能进行测试,并对三种供热系统的经济环境效益进行分析。试验结果表明,试验条件下,三种供热系统的修正后一次能源利用率分别为93.3%、92.8%、103.9%,与燃气供热系统相比,节能率分别为3.8%、3.2%和15.6%,年运行费用可节约275、236、1 016￥,每年减排CO₂为123.00、106.00、455.00 kg。     

燃气机热泵供暖过程的计算与分析

对驱动燃气机热泵的发动机余热产生规律进行了实验研究，并对燃气机热泵建立了一个计算模型。通过计算，分析了发动机余热对燃气热泵供暖过程的影响，着重分析了部分负荷下燃气机热泵的供暖过程的特点。以上海地区的气候条件和能源价格为基础，对燃气机热泵供暖的能耗和运行费用进行了分析比较。     

沼气发动机驱动的热泵能源利用率计算

沼气发动机驱动的热泵(BHP)是一种节能环保型装置,与电动压缩式热泵相比,其主要动力源不同.该装置能充分回收利用沼气发动机余热.通过对BHP系统的构建及一次能源利用率(PER)的计算,分析了BHP系统的经济性及其对环境保护的作用.结果表明:不论从节能还是从环保方面考虑,BHP系统都具有明显的经济价值和环保效益.     

燃气机热泵的热力学分析

燃气机热泵是以燃气机作为动力来驱动的压缩式热泵。对燃气机热泵的热力学第一定律、Yong分析和能级平衡理论分析结果表明：其一次能源利用率可达1.76，Yong效率为0.291，能级平衡系数为0.394。与电动热泵等其他供热装置相比，燃气机热泵有着较高的热力学完善性，是一项高效节能技术。由于能级平衡理论分析考虑了Wu的作用，而热泵供暖时其性能系数的提高主要是利用了环境热量，所以建议采用能级平衡理论来分析评价热泵的性能。     

我国燃气热泵空调的应用前景探讨

结合我国能源结构现状和发展趋势 ,重点介绍燃气热泵空调低能耗、优越的冬季适应性和高效环保的优点 ,并分析探讨了燃气热泵空调的发展前景     

燃气驱动的溴化锂吸收式热泵应用案例分析

针对山东省某大型燃气热水锅炉排烟温度较高与耗气量过大的问题,提出采用燃气直燃型吸收式热泵回收烟气余热、减少排烟损失,并给出燃气锅炉与吸收式热泵烟气余热回收方案的运行流程.根据天然气热平衡、排烟温度与天然气利用率、热泵COP值以及最大负荷利用小时数等,全面分析回收烟气余热节能效果.通过1个采暖季理论计算研究和实测对比分析...     

燃气机热泵冷热电三联供系统热经济学分析

采用热经济学分析法对一台燃气机热泵冷热电三联供系统进行分析,对不同转速,蒸发温度,冷凝温度和天然气价格4项影响因素条件下,子系统火用成本差、火用经济因子和总系统的火用经济系数的计算分析,指出了燃气机热泵冷热电三联供系统需要改进之处,针对燃气机热泵冷热电三联供系统的设计需要注意传动比的合理设置问题,并且得出了燃气机热泵冷热电三联供系统在中国具有广阔的应用空间的结论.     

燃气机热泵变负荷特性的试验研究

燃气机热泵是一项高效节能技术，在试验条件下其一次能源利用率PER为1．13～1．79。为了解交负荷时燃气机热泵的性能，通过试验得到了燃气机热泵的发动机负荷特性、发动机余热回收和燃气机热泵的总体特性曲线。结果表明：随着发动机转速的增加，燃气机热泵的COP和PER是下降的，但下降的幅度较为平缓，且保持较高的数值。通过对IPL Vcop值的分析，发现燃气机热泵的IPL Vcop比热泵系统的大，这说明燃气机热泵的部分负荷性能好，可以很好地实现交负荷运行。     

燃气热泵系统在过渡季节制备生活热水的性能研究

研究了燃气热泵(GHP)系统在过渡季节制备生活热水的性能特性,分析了发动机余热回收对GHP系统性能的影响。在不同环境温度(15～24℃)和进水温度(37.7～47.8℃)下,考察回收与不回收发动机余热模式对生活热水制热量■、耗气功率(P_gas)及一次能源利用率(r_PER)的影响规律。结果表明,随着环境温度的升高,P_gas减小,而■和r_{PE R}呈现递增的趋势;随着进水温度的升高,Pgas增大,而■和r_PER呈现递减的趋势。其中环境温度20～24℃与进水温度37.7～47.8℃为Q_h的不敏感区间,在环境温度为24℃和进水温度为37.7℃条件下,r_PER高达2.004。GHP系统的余热回收量分别占总制热量和发动机总余热的25.00%～30.16%和62.17%～71.56%,系统的余热利用率高。     

太阳能热泵系统简介

太阳能与热泵相结合的技术是新能源利用技术发展的一个重要方面.文章介绍了太阳能热泵的基本知识,并分析了太阳能和热泵相结合应用的特点,并对其经济性作了初步分析.     

Exergetic performance evaluation of heat pump systems having various heat sources

In this study heat pump systems having different heat sources were investigated experimentally. Solar‐assisted heat pump (SAHP), ground source heat pump (GSHP) and air source heat pump (ASHP) systems for domestic heating were tested. Additionally, their combination systems, such as solar‐assisted‐ground source heat pump (SAGSHP), solar‐assisted‐air source heat pump (SAASHP) and ground–air source heat pump (GSASHP) were tested. All the heat pump systems were designed and constructed in a test room with 60 m² floor area in Firat University, Elazig (38.41°N, 39.14°E), Turkey. In evaluating the efficiency of heat pump systems, the most commonly used measure is the energy or the first law efficiency, which is modified to a coefficient of performance for heat pump systems. However, for indicating the possibilities for thermodynamic improvement, inadequate energy analysis and exergy analysis are needed. This study presents an exergetic evaluation of SAHP, GSHP and ASHP and their combination systems. The exergy losses in each of the components of the heat pump systems are determined for average values of experimentally measured parameters. Exergy efficiency in each of the components of the heat pump systems is also determined to assess their performances. The coefficient of performance (COP) of the SAHP, GSHP and ASHP were obtained as 2.95, 2.44 and 2.33, whereas the exergy losses of the refrigerant subsystems were found to be 1.342, 1.705 and 1.942 kW, respectively. The COP of SAGSHP, SAASHP and GSASHP as multiple source heat pump systems were also determined to be 3.36, 2.90 and 2.14, whereas the exergy losses of the refrigerant subsystems were approximately 2.13, 2.996 and 3.113 kW, respectively. In addition, multiple source heat pump systems were compared with single source heat pump systems on the basis of the COP. Exergetic performance coefficient (EPC) is introduced and is applied to the heat pump systems having various heat sources. The results imply that the functional forms of the EPC and first law efficiency are different. Results show that Ex_loss,total becomes a minimum value when EPC has a maximum value. Copyright © 2008 John Wiley & Sons, Ltd.     

复合式土壤源热泵系统设计

设计了一套复合式土壤源热泵性能实验台,采用冷却塔作辅助冷源、太阳能热水器作辅助热源,能够实现冬季供暖、夏季供冷、一年四季提供60~80℃生活热水的功能。给出了系统中热泵机组、空调末端设备、冷却塔、水泵、太阳能热水器等主要部件的选型计算方法,经搭建好的土壤源热泵性能实验台运行测试,制冷和制热效果良好,同时也解决了土壤热平衡问题。     

Chemical heat pump using heat of reversible catalytic reactions

One of the most important objects of research in the field of energy conservation is development of a high temperature heat pump for the industrial sector. In this framework this paper introduces a new concept of heat pump, which is a hybrid between a compressor and chemical heat pump, where instead of the latent heat of liquids, the proposed system uses the heat of gaseous catalytic reversible reactions (type A → B + C). This paper proposes a simple scheme with a mathematical model for the calculation of the parameters necessary to qualify the behaviour of the Heat Reaction Chemical Heat Pump (HRCHP). The Coefficient of Performance (COP) is calculated as a function of the temperature of the heat source, the temperature to which the pump upgrades the heat and the conversion of the chemical reaction. A more optimized scheme is prospected.     

Analysis of a heat pump with solid desiccant tube bank

In this paper, the analysis of silica gel formed in a staggered tube bank arrangement for the reduction of energy consumption in a heat pump dehumidifier is presented. The mathematical models for the desiccant and the heat pump have been developed. The simulated results agree quite well with those of the experiments. The desiccant could reduce the heat pump load by about 7–20 per cent at the inlet air conditions of about 30–50°C and 70–90 per cent RH. Copyright © 2002 John Wiley & Sons, Ltd.     

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。     

Performance assessment of contact heat pump drying

A comparative analysis is presented of a novel plate‐type isothermal heat pump dryer and a conventional adiabatic heat pump dryer. The energy performance and drying capacity of each dryer type is investigated subject to operational constraints on the maximum acceptable relative humidity and temperature of air passing over the product. The analysis demonstrates that for applicable products, a significant opportunity exists for improving the energy efficiency of heat pump drying, by a factor of 2–3 times compared with current adiabatic heat pump dryers. The moisture extraction rate is also increased in the contact heat pump dryer, by a similar factor. However, these improvements are shown to be sensitive both to the impact of product thickness on heat transfer and to the relative humidity constraint. Copyright © 2010 John Wiley & Sons, Ltd.     

Improving heat recovery using retrofitted heat pump in air handling unit with energy wheel

The world is facing a challenge to reduce energy use to meet the environmental goals set for the future. One factor that has a great impact on the energy performance of buildings is the ventilation losses. To handle these losses, heat recovery systems with rotating heat exchanger are often implemented. These systems have been shown to recover about 60–70% of the energy in the exhaust air on an annual basis.After a heat recovery system is installed it is hard to improve the efficiency of the installed recovery system with an acceptable economic payback period. In the present paper one way to improve the energy performance of a building with this type of heat recovery system by the use of a heat pump is investigated by simulations in TrnSys.The heat pump system is arranged so that the evaporator is connected to a heat exchanger mounted in the exhaust airstream after the energy wheel, and the condenser of the heat pump is mounted so that the temperature of return water from the heating coil is increased.The simulations show that there is a possibility to increase the heat recovery rate of the air handling unit in a significant way by retrofitting a heat pump to the system.     

A new concept in gas-fired heat pump reversed rectification heat pump

The reversed rectification heat pump (RRHP) is a novel type of absorption heat pump developed at Laboratoire des sciences du génie chimique (LSGC) in the research group of Professor Le Goff. The distinctive characteristic of the RRHP is that both the separator and the absorber are multi-stage gas contacting units of a type commonly used in the process industry and each composed of the multi-stage contactor, an evaporator and a condenser. The separator is a conventional rectification unit in which the working fluid is separated into a rich and a lean phase which are recombined in the absorber. The absorption is an exact reversal of the rectification, both units having inverted flow diagrams; for this reason the absorption is refered to as reversed rectification. This heat pump can produce simultanious heat and cold and provides significant primary energy savings and reduction of harmful environmental effects.     

Heat-pipe enhanced solar-assisted heat pump water heater

A heat-pipe enhanced solar-assisted heat pump water heater (HPSAHP) is studied. HPSAHP is a heat pump with dual heat sources that combines the performance of conventional heat pump and solar heat pipe collector. HPSAHP operates in heat-pump mode when solar radiation is low and in heat-pipe mode without electricity consumption when solar radiation is high. HPSAHP can thus achieve high energy efficiency. A prototype was designed and built in the present study. An outdoor test for a HPSAHP in the present study has shown that COP of the hybrid-mode operation can reach 3.32, an increase of 28.7% as compared to the heat-pump mode COP (2.58).