溶液调湿新风机组与地源热泵相结合的空调设计

以上海虹桥产业楼空调系统为例,介绍了溶液调湿新风机组与地源热泵系统的设计,重点介绍了干式末端设备、冷热源主机、地埋管系统、空调水系统及自控系统设计的要点.根据实际运行调试情况,对冷热源水系统、干式风机盘管、高温型地源热泵机组、免费冷热源板式换热器、地源热泵与冷水机组的运行策略及生活热水应用进行了经验总结.     

Field performance measurements of a heat pump desiccant unit in dehumidification mode

The variable refrigerant volume (VRV) air conditioning system needs to be operated in conjunction with a ventilation system, because the VRV system cannot provide any fresh air. The common ventilation unit used with the VRV system is the heat recovery ventilation (HRV) unit. In this study, a new ventilation unit, a self-regenerating heat pump desiccant (HPD) unit, was introduced and the characteristics of the HPD unit was experimentally investigated over a wide range of operating conditions in a field performance test. In addition, the energy saving contribution of the HPD and HRV units to the VRV system was compared. It was found that the HPD unit maintained the target indoor humidity ratio of 10 g/kg throughout the cooling season resulting in a better indoor thermal comfort than the HRV unit. Besides, it was found that the outdoor unit of the VRV system consumed 26.3% less energy for the operation in conjunction with the HPD unit as compared to the operation in conjunction with the HRV unit.     

A new heat pump desiccant dehumidifier for supermarket application

Recently a new equipment for dehumidification was put onto the market. It is a self-regenerating liquid desiccant cooling system able to dehumidify, heating or cooling the ambient air by an electric heat pump that is a part of the equipment. Its operation is here studied in a supermarket application where air temperature and relative humidity play a very important role and the air-conditioning becomes necessary not only to assure a suitable thermal comfort, but also to make the refrigerated display cabinets operate properly. In this paper possible energy savings, compared to a traditional mechanical dehumidification, are evaluated by means of a numerical model that simulates a typical Italian supermarket.     

Experimental investigation of a novel desiccant cooling system

Desiccant based air conditioning systems are a suitable way to improve indoor air quality due to its superior humidity control. In this study, a novel desiccant based air conditioning system is designed and tested experimentally to improve the indoor air quality and reduce energy consumption. In the system studied, a heat exchanger, which is not used in this type of systems, for pre-heating the regeneration air with exhaust air is used. This paper reports results of initial operation and operational procedures. The performance of the system and its components is discussed.     

Analysis on performance of a novel frost-free air-source heat pump system

Heating capacity of an air-source heat pump (ASHP) system often decreases due to frost on the air-side heat exchanger (evaporator) when the air temperature drops in winter. If the amount of frost accumulates to a certain value, performance of the system will degrade. Therefore, defrosting mode needs to be operated periodically. In order to solve the above problems, heat transfer enhancement or advanced defrosting methods should be adopted, but all these methods cannot solve the problems mentioned in essence. A novel frost-free air-source heat pump system is proposed, the new system can realize heating which does not need defrost in winter. In this new system, extracting heat process from environment includes two steps: the first one is extracting heat from the environment and then to the solution, the second one is releasing heat to the evaporator from the solution, avoiding frosting on the evaporator surface. A theoretical model is established to analyze the performance of the system. Results indicate that the novel system can operate more efficiently than the conventional air-source heat pump in winter. In addition, the new system does not need to run in defrosting mode periodically.     

Experimental study of a heat pump system with flash-tank coupled with scroll compressor

A heat pump system with a flash-tank coupled with a scroll compressor is compared with a system with a sub-cooler. The heat pump performance was measured experimentally. The heating capacity of the prototype decreased as the evaporation temperature decreased, but the decrease was much slower than that of a conventional air-source heat pump. The power input varied slightly with the evaporation temperature. The heat pump system with a flash-tank is more efficient than the system with a sub-cooler at low ambient temperatures, so it will be very useful as a small capacity air-source heat pump.     

一种新型液体除湿空调的应用

分析了常规液体除湿空调的不足,开发了一种新型液体除湿空调装置,介绍了其系统原理及流程。在上海高温高湿的气候条件下的实际应用表明该系统在节能和低品位能源利用方面有重要意义。     

溶液全热回收装置与热泵系统结合的新风机组

提出了一种以溶液为媒介的全热回收装置和热泵系统相结合的新风处理机。安装于某医院的新风机性能测试结果表明：测试条件下,新风机夏季性能系数为6．3～7．3,冬季性能系数为4．7～5．0。新风机中吸湿溶液能去除空气中多种污染物,可避免新风和室内排风之间的交叉污染。     

Field performance measurements of a heat pump desiccant unit in heating and humidification mode

In this study, a novel self-regenerating electric vapor compression heat pump desiccant (HPD) unit operated in the heating and humidification mode during the winter season is introduced. The HPD unit was installed in an office suite for the field test. The performance of the HPD unit and the provided indoor conditions were measured over a wide range of operating conditions. The target indoor humidity ratio was set to 4.4 g/kg, which is the minimum required indoor humidity ratio for a comfortable indoor environment indicated in the ASHRAE winter thermal comfort zone. The seasonal comparison revealed that even though 77.7% of all outdoor humidity ratio data was lower than 4.4 g/kg, 78.2% and 85.8% of all the indoor humidity ratio data of each room were found to be higher than 4.4 g/kg. In addition, due to the significant sensible capacity of the HPD unit, the indoor temperatures could be maintained within 20-25 °C. These results prove that the HPD unit not only properly humidifies the indoors without using any additional water source, like the conventional humidifier, but also helps to keep the indoor temperature at the desired temperature levels.     

某大型公共建筑江水源与地源热泵联合系统设计

结合工程实例介绍了江水源热泵和地源热泵系统的应用,重点介绍了联合系统的冷热源系统设计,并分析了联合系统的节能性.     

热泵驱动的双级溶液调湿新风机组原理及性能测试

介绍了一种新型热泵驱动的双级溶液调湿新风机组的工作原理和全年运行方式,重点介绍和分析了该机组主要部件的实测性能数据.测试结果表明,双级溶液全热回收单元的全热回收效率和潜热回收效率分别为55%左右,而新风机组在满负荷工况下整机COP为5.0,部分负荷下可超过5.9,其中的热泵制冷系统在满负荷工况下COP为4.01,部分负荷下可超过5.72,溶液热回收板式换热器的显热回收效率在80%以上.测试分析了机组进行新风处理的整体性能,指出了在再生单元补水的重要性.     

排热驱动的吸附式除湿空调系统

分析了现有吸附式除湿空调系统存在的问题,详细阐述了一种新型吸附式除湿空调系统的构造、运行原理、性能特性,并对实验结果进行了讨论,为该空调系统的应用提供基础数据及设计指南。     

Optimisation of a heat pump space heating system

Because the heat pump has a very high capital cost compared with other forms of space heating, and also because the peak space heating demand in the U.K. only occurs for a few hours in the year, it has become recognised practice to install low capital cost supplementary electric heating to meet peak demands. A technique is described which optimizes the mix of heat pump and supplementary capacity to minimize the total cost of operation. A simulation model is employed which uses a weather tape containing hourly outside air temperatures to generate a space heating demand profile for a building of known thermal characteristics. The technique specifically allows the examination of intermittent heating, and in this paper is applied to a small factory operating on a variety of shift patterns. This application is of particular interest because it considers the effect of maximum demand charges on the economics of heat pump space heating systems. It is concluded that the optimum heat pump capacity depends strongly upon the length of shift, and that optimum oversizing of the heat pump system for intermittent heating appears to be lower than for conventional heating systems as a result of maximum demand pricing.     

一种新型地热井下换热器-热泵联用供热系统的热力分析

建立了该供热系统的热力学模型,推导出了供热负荷与设计参数、运行参数、环境温度的关系式.通过理论计算,分析了添加热泵与未加热泵两种工况下,散热器表面积、循环水流量、环境温度等对井下换热器性能及供热系统供热量的影响.     

Integration of variable refrigerant flow and heat pump desiccant systems for the heating season

Integration of the variable refrigerant flow (VRF) and heat pump desiccant (HPD) systems was investigated in a field performance test for a heating season. The HPD systems use only the moisture in the outdoor air and return air to humidify the indoors during ventilation in the heating season. Three different operating modes: non-ventilated, HPD ventilation assisted and HPD ventilation-humidification assisted VRF systems were investigated. It was found that the VRF systems provided an average of 93.5% of the total heating energy for the HPD ventilation assisted mode. The remainder was the recovered heat by the HPD systems during ventilation. The VRF systems provided an average of 46.8% of the total heating energy for the HPD ventilation-humidification assisted mode. The remainder was covered by the HPD systems which provided additional sensible and latent heating. Overall, among the three operating modes, it is concluded that the HPD ventilation-humidification assisted VRF outdoor units consume less energy than the HPD ventilation assisted ones (about the same energy as the non-ventilated ones), while providing the best indoor thermal comfort and indoor quality conditions. For the total system, the HPD ventilation-humidification assisted VRF systems consume less energy than the HPD ventilation assisted ones.     

Implementation of a building foundation heat transfer model in EnergyPlus

In this article, a two-dimensional transient ground-coupled numerical model for slab-on-grade foundation is developed and integrated into EnergyPlus. A verification analysis is first presented to ensure that the developed building foundation heat transfer module is properly implemented within EnergyPlus. Then, predictions from the developed model are compared with those obtained from a simplified building foundation model currently used in EnergyPlus. Finally, the impact of several foundation insulation configurations on the annual variation of both heating and cooling loads is investigated for a one-storey single-family ranch house. The results show that the developed foundation heat transfer module accounts more accurately for the effects of the ground thermal mass than the foundation model currently used in EnergyPlus. In particular, it was found that annual heating and cooling loads can be overestimated by over 20% for a typical residential building if ground-coupled heat transfer calculations are not fully integrated in EnergyPlus.     

芜湖地区U型管地源热泵系统试验研究

为研究芜湖地区地源热泵系统的可适用性,对U型管地源热泵系统换热能力进行试验研究,试验分为散热试验和取热试验。经试验得出,采用U型管地源热泵系统相对于传统空调系统更节能、更环保,在芜湖地区有广阔的开发利用前景。     

一种新型热泵换热器系统

通过对现有热泵系统的分析,提出了一种新的热泵室外机系统.该系统以盐水为冷媒,采用二级换热结构,可以有效防止冬季供暖过程中室外机的结霜.     

天津公馆：污水源热泵节能系统应用

日前,天津市最受瞩目的污水源热泵空调系统工程项目——建筑面积为5．4万平方米的天津公馆由天津市金大地能源工程技术有限公司建成并投入运行。通过连续一个时期的调试及低温运行,供暖、供热水效果显著,已完全满足供热要求。此项目的成功运行开创了天津市利用原生污水源热泵技术为居民住宅提供绿色采暖的新纪元,实现了天津市节能减排的新突破,具有极大的推广应用价值。“天津公馆”项目已被国家建设部和财政部列为可再生能源建筑应用示范项目并得到资助。     

液体除湿与排风热回收相结合的新风处理系统

该系统能实现温度湿度独立控制,提高空调冷水温度。介绍了液体除湿独立处理新风和液体除湿与全热换热器共同处理新风的焓湿图和系统流程图。结合对某工程的节能改造,分析了节能效益及减排量。结果表明,应用该系统在设计工况下可获得冷量1.36GJ/h,CO2减排量132.5kg/h,节能减排效果显著。