上海地区应用转轮式全热交换器的经济分析

在建筑物的空调负荷中,新风负荷所占的比例是很大的。因此,采用热交换器从排风中回收能量是空调系统节能的有效方法之一。这种热回收系统在国外应用得很多,仅瑞典产品“万得”转轮式全热交换器已有3     

用离子交换树脂作为吸湿材料的新型转轮型全热交换器

全热交换器,顾名思义是一种即可进行显热、交换也可进行潜热交换的热交换器.由于它可以同时回收空调房间因换气而损失热能中的显热和潜热,在楼宇空调新风换气系统的节能过程被广泛应用.本文介绍了转轮型全热交换器的运转原理,分析阐述了现行的以各种吸附剂为吸湿材料的全热交换器在使用中有时会发生的异味现象(又称臭气转移现象)的发生机理.并对研发的可以避免异味现象发生的用离子交换树脂作为吸湿材料的新型全热交换器与现行的以各种吸附剂为吸湿材料的全热交换器在传热性能、臭气转移发生状况等方面的对比实验研究结果作了详细介绍.     

某设计实例中看全热交换器在空调机组中的使用

全热交换器在全空气空调系统中的应用取得了良好的节能效果。     

瑞典菲达公司的排风热回收设备

1981年9月,瑞典能源展览会在北京展览馆展出。瑞典菲达(F1akt)通风空调设备公司展出了该公司在通风、空调节能方面的技术发展情况并进行了技术座谈。一、排风热回收的概况对于通风空调系统来说,采用再循环空气当然是最好的节能方式。但是,由于卫生要求,往往需要部分或全部排除室内空气,补充室外新风。若能回收排风中的热能,用以预热新风,就能大大减少新风耗热。以采用转轮式全热交换器为例,其效果见表1。     

全热换热器应用于空调系统节能的研究进展

空调系统的大量使用导致了空调能耗所占社会总能耗的比重越来越大。因此,降低空调系统的能耗对降低建筑物耗能、节约能源有重要意义。全热交换器是一种可以降低空调负荷、节约系统能耗、提高系统效率的高效节能产品。它有效地解决了改善室内空气品质与空调节能之间的矛盾,在空调系统节能领域中是不可替代的。     

全热换热器应用于空调系统节能的研究进展

空调系统的大量使用导致了空调能耗所占社会总能耗的比重越来越大。因此，降低空调系统的能耗对降低建筑物耗能、节约能源有重要意义。全热交换器是一种可以降低空调负荷、节约系统能耗、提高系统效率的高效节能产品。它有效地解决了改善室内空气品质与空调节能之间的矛盾，在空调系统节能领域中是不可替代的。     

板式全热交换器应用研究

本试验对板式全热交换器的显热和全热效率进行测试,分析温差、湿度差和风量对效率的影响;并结合试验结果分析了其在空调系统中应用的节能性。     

带热回收的新风空调系统在医院建筑中的应用分析

针对一个独立新风、集中排风并带全热交换器能量回收的医院输液室空调系统,实验测试了空调系统的能耗,计算了全年节能潜力,并通过测量室内CO2浓度,研究了通风对室内空气质量的改善程度。结果表明,该空调系统在改善室内空气质量的同时可以节约能量,是医院建筑的理想空调系统。     

转轮热回收系统节能初探

简要介绍了一种节能方式——转轮式热回收系统在空调系统中的应用,阐述了此系统的工作和节能原理.并以上海某工程为例,详细分析冬夏季工况的热回收量和经济性.经分析后认为转轮式热回收不但可以节省运行费用,而且可以节约空调系统的初投资,在空调节能方面具有广阔的应用前景.最后总结阐述转轮式热回收机组在设计中应注意的问题,为今后的工...     

膜法空调除湿的原理与研究进展

介绍了膜材料、膜法除湿工艺、膜法除湿在空调系统中的应用的研究进展.分析表明,几种新型的除湿工艺有较好的发展前景;膜全热交换器用于空调系统中的除湿可以回收60%～76%的排气余热,有较好的节能效果.     

Theoretical simulation and experimental research on the system of air source energy independence driven by internal-combustion engine

Presents a new system of air source energy independence driven by internal-combustion engine (EIICE), which used natural gas or other fuels as an independent input energy, and could provide the heating, cooling and hot water for the buildings efficiently. It also could provide electricity for electric equipments of the system. The performance of air source EIICE system was investigated theoretically and experimentally. The experimental and simulation results indicated that the heat capacity of plate heat exchanger (P-HE), heat recovered from exhaust gas heat exchanger (EG-HE), input power of compressor, output power of engine and fuel consumption increased with the increase of the rotary speed, water flow rate of the P-HE and evaporation temperature. Heat recovered from the cylinder jacket heat exchanger (CJ-HE) increased with the increase of the rotary speed and evaporation temperature, but decreased with the increase of the water flow rate of P-HE. The coefficient of performance (COP_t) and primary energy ratio (PER_t) of air source EIICE system also increased with the increase of the water flow rate of P-HE and evaporation temperature, but decreased with the increase of the rotary speed.     

蒸发冷却空调新风系统的全年应用研究

结合干热、严寒或寒冷地区全年气候特点及冬夏季建筑能耗特性,通过逐时新风能耗模拟计算,得到设置热回收装置的全年用蒸发冷却空调系统冬季新风节能量远大于夏季节能量,选用热回收装置时应重点关注冬季热回收效率,各类热回收装置中转轮热回收装置全年节能量最大,节能效果最好。基于此,深入分析了蒸发冷却空调系统冬夏季新风加湿需求、新风量变化范围和水系统管径选择,给出了全年用蒸发冷却空调机组冬季运行的防冻措施。     

Membrane heat exchanger in HVAC energy recovery systems, systems energy analysis

The thermal performance of an enthalpy/membrane heat exchanger is experimentally investigated. The heat exchanger utilizes a 60gsm Kraft paper as the heat and moisture transfer surface for HVAC energy recovery. The heat exchanger sensible, latent and total effectiveness have been determined through temperature and moisture content measurements. The annual energy consumption of an air conditioner coupled with an enthalpy/membrane heat exchanger is also studied and compared with a conventional air conditioning cycle using in-house modified HPRate software. The heat exchanger effectiveness are used as thermal performance indicators and incorporated in the modified software. Energy analysis showed that an air conditioning system coupled with a membrane heat exchanger consumes less energy than a conventional air conditioning system in hot and humid climates where the latent load is high. It has been shown that in humid climate a saving of up to 8% in annual energy consumption can be achieved when membrane heat exchanger is used instead of a conventional HVAC system.     

板翅式全热交换器应用于分散独立空调系统中的探讨

通过对板翅式全热交换器的结构和原理,热回收效率及其经济性的分析,得出在分散独立系统中使用板翅式全热交换器是改善室内空气品质,节约能源消耗的一项行之有效的措施。     

Mass Transfer Of Contaminants In Rotary Enthalpy Exchangers

The present work is a study of reentrainment of a tracer gas formaldehyde via six rotary air-to-air heat exchangers (all enthalpy exchangers) in the northern part of Sweden. Five exchangers installed in office buildings and one in a day-care centre were included in the study. Formaldehyde in indoor was used as a monitor pollutant and was determined in air samples collected in the ducts at four positions around the rotor of the exchanger, in the supply-air duct and in the exhaust-air duct. Air sampling of homogeneous duct air was performed simultaneously at the four positions using 2, 4-dinitrophenylhydrazine-impregnated glass fibre filters. The sample analysis of formaldehyde was made by high-performance liquid chromatography. The reentrainment of formaldehyde was calculated and found to be 1-9%. These results show that a rotary heat exchanger can be used in buildings where activities produce low levels of air pollutants, provided that the exchanger is properly installed and maintained.     

Residential air-to-air heat exchangers: Performance energy savings,and economics

Residential energy consumption can be decreased if air infiltration is reduced by constructing houses more tightly. In some cases, however, reduced air infiltration can lead to problems with indoor air quality (e.g., excess humidity and high levels of indoor-generated air contaminants). One solution to this problem is to install a residential air-to-air heat exchanger. The heat exchanger provides a controlled supply of ventilation which counteracts the adverse effects of reduced infiltration. In addition, the heat exchanger recovers much of the energy that would normally be lost when ventilation occurs by air infiltration. Thus, by employing heat exchangers in low-infiltration houses, it is possible to save energy without sacrificing indoor air quality.This paper discusses the performance of residential heat exchangers and summarizes results from tests of several models. It also compares the energy consumed, during the heating season, in low-infiltration houses with heat exchangers, with the energy consumed in typical houses in four cities throughout the United States. For each city, a cost-benefit analysis is performed from the point of view of a home-owner. Houses with natural gas, oil, and electrical heating systems are considered. Our analysis indicates that the energy required to heat ventilation air in homes employing heat exchangers is 5.3 – 18.0 GJ less than the energy required to heat ventilation air in typical homes. In homes with heat exchangers, the heat exchanger's fan system required 2.2 – 3.6 GJ of electrical energy during the heating season. The net present benefit for homes employing heat exchangers, when compared with typical homes, ranged from —$1350 to +$2400 and discounted payback periods ranged from five to over 30 years. The cost-effectiveness of employing heat exchangers was found to be highly affected by climate, type of heating fuel, heat exchanger performance, and ventilation rate.     

Field performance of an energy pile system for space heating

This paper describes the field performance of air conditioning with an energy pile system, which was applied to the pile foundations of an actual building for the purpose of reducing the cost of the underground heat exchanger. First, the building for both office and residential use, for which a space heating and cooling system using friction piles was installed, was built in Sapporo in December 2000. Second, three tests were carried out to specify the design of a heat exchanger inside the pile, and a U-tube type underground heat exchanger was adopted from the viewpoint of energy efficiency and installation costs. Long-term space heating operation measurements indicated that the seasonal average temperatures of brine returning from the underground and pile surfaces were 2.4 and 6.7 °C, respectively. The average coefficient of performance for space heating was quite high at 3.9, and the seasonal primary energy reduction rate compared with a typical air conditioning system reached 23.2%.     

北京地区夏季工况新风换气机能耗回收分析

新风能耗要占夏季空调负荷的20%～40%,新风回收越来越受到人们的重视,新风换气机得到了一定程度的普及.针对北京夏季新风负荷的特点,对市场上流行的新风换气机进行能耗回收分析,得出夏季工况显热通风换气机回收效率极低,全热通风换气机能减少一半的负荷.     

Theoretical performance assessment of an integrated photovoltaic and earth air heat exchanger greenhouse using energy and exergy analysis methods

In this paper, a simplified mathematical model develops to study round the year effectiveness of photovoltaic/thermal (PV/T) and earth air heat exchanger (EAHE) integrated with a greenhouse, located at IIT Delhi, India. The solar energy application through photovoltaic system and earth air heat exchanger (EAHE) for heating and cooling of a greenhouse is studied with the help of this simplified mathematical model. Calculations are done for four types of weather conditions (a, b, c and d types) in New Delhi, India. The paper compares greenhouse air temperatures when it is operated with photovoltaic/thermal (PV/T) during daytime coupled with earth air heat exchanger (EAHE) at night, with air temperatures when it is operated exclusively with photovoltaic/thermal system (PV/T) and earth air heat exchanger (EAHE), for 24 h. The results reveal that air temperature inside the greenhouse can be increased by around 7-8 °C during winter season, when the system is operated with photovoltaic (PV/T), coupled with earth air heat exchanger (EAHE) at night. From the results, it is seen that the hourly useful thermal energy generated, during daytime and night, when the system is operated with photovoltaic (PV/T) coupled with earth air heat exchanger (EAHE), is 33 MJ and 24.5 MJ, respectively. The yearly thermal energy generated by the system has been calculated to be 24728.8 kWh, while the net electrical energy savings for the year is 805.9 kWh and the annual thermal exergy energy generated is 1006.2 kWh.