共查询到20条相似文献，搜索用时 218 毫秒
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Based on the contrast experiment, the condition of air-cooled heat pump operating indoors is analyzed in this paper.The operating performance corresponding to such conditions is gained.The ventilation condition of stable operation for air-cooled heat pump is found.At the same time, the experimental results based on actual work are proved. indoors; air-cooled heat pump; ventilation 相似文献
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The vertical U-tube ground-coupled heat pump system provides cold and heat for the controlling of indoor environment. Under the air-conditioning condition, the vertical U-tube ground-coupled heat pump system with heat recovery can provide domestic hot water. The influence of supplying domestic hot water on the heat transfer performance of ground heat exchangers is different under different operating modes in summer and winter. Through a project design of ground-source heat pump system, the influence of supplying domestic hot water under heat storage mode on the heat transfer performance of ground heat exchangers in summer and winter is respectively analyzed. The dynamic performance of heat exchangers under different working conditions is analyzed, and through numerical calculation, the heat transfer performance parameters of ground heat exchangers under different operating modes are obtained. From the calculation results, the adjusting methods based on the load characteristics of this project represent. 相似文献
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Based on an actual ground source heat pump system in hot summer and cold winter area, the system operation parameters were tested for 6 years under the state of using cooling tower for cooling in summer but the ground heat exchanger and fire pool for heating in winter. A three dimensional (3D) tube group model was established, and the thermal balance analysis and calculation of the ground temperature distribution around the ground heat exchanger were conducted by the numerical calculation. According to the comparison between the test data and the theoretical results, the influencing factors of the ground adjustment ability were obtained. 相似文献
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Intermittent operation can affect the heat exchange performance of the vertical ground source heat pump system, thereby affecting life cycle cost (LCC) of the ground source heat pump system. The simulation analysis on the hourly load of an office building is implemented by using the DeST software.The heat exchange model of vertical ground heat exchanger pipe-group and energy consumption model of per part of heat pump system are established. Through the comparison between calculation results of continuous operation for 15 years and calculation results of intermittent operation 15 years of the heat pump system, it can be concluded that the LCC value of intermittent operation decreased by 13.45%,relative to the LCC value of continuous operation, and the average energy saving rate of intermittent operation mode is 17.20% in the entire life cycle. Intermittent operation mode can effectively improve energy efficiency of the ground source heat pump system and reduce the LCC value. 相似文献
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为了快速评价寒地冬小麦耐低温特性,通过室内低温处理和自然条件种植两种方式,采用调查低温下植株成活率和反应植株受伤害程度的电导法,研究抗寒性不同的冬小麦植株低温下其受伤害程度的差异。结果表明,实验室内抗寒品种低温-24℃处理5天后植株受伤害程度一致,而不抗寒品种-18℃处理5天后植株受伤害程度一致;室内抗寒品种-12℃处理7天其成活率低于50%,而不抗寒品种-12℃处理1天其成活率低于50%。由此得出,室内种植和室外种植的冬小麦植株经冷冻后其成活率差异不显著;抗寒品种‘东农冬麦1号’的半致死温度为-32℃,不抗寒品种‘济麦22’的半致死温度为-15℃。 相似文献
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In this paper the low-temperature hydraulic floor heating system of a residence in Chongqing was tested. The influence of this system and the heat pump air conditioning system on indoor thermal comfort and operation cost was analyzed and compared. The effect of heat dissipation by radiation and convention of the floor was analyzed. It shows the feasibility and advantage of floor heating system in Yangtse River Region. 相似文献
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重庆村镇空气源热泵供暖系统夜间性能实测分析 总被引：1，自引：0，他引：1
针对重庆山地村镇迫切的供暖需求,选取该地区典型村镇搭建了空气源热泵供暖系统实验平台,分析了空气源热泵系统性能影响因素,并从供回水温度、系统耗电量、供热量、性能系数COP等角度对运行过程中的阶段特性(启动、稳定运行及全阶段)进行阐述,发现系统在3个阶段特点差异很大：启动阶段初始温度对COP影响较为明显,除霜时系统性能下降25%;稳定阶段特性与初始温度无关,室外条件较好时,降低设定温度,COP提高明显;总体来看,启动阶段COP最高,全阶段次之,稳定阶段COP最低。 相似文献
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The forms of water transportation, arrangement and operation of pumps contribute to the water transportation energy consumption, which influences the energy-saving effect of surface water source heat pump. The relation between the pumping height and energy consumption of pumps is found by analyzing the model of pump energy consumption. The concept and calculation of critical pumping height is presented considering the limited rate of system energy efficiency. Based on the principle that the pump power changes with water flow rate, the determination of pumps arrangement of one or two stage pumps is described with a concrete example. The influence of water flow rate on heat pumps and water pumps is analyzed, and the energy efficiency of constant and variable water volume are compared. The operation way of this example is concluded for the optimal system energy efficiency. It is found that there is a critical pumping height for the energy-saving effect of surface water source heat pump compared with the traditional system. Moreover, the operation strategies should be determined by the system optimal model since the energy consumptions proportions of heat pumps and water pumps are variable. 相似文献
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Annual Energy Consumption and Feasibility Assessment of Ground -Source Heat Pump in Residential Building in Fuzhou City 
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下载免费PDF全文 This paper describes the annual energy consumption and economic assessment of air-source heat pump(ASHP) and ground-source heat pump(GSHP),based on hourly building load of typical house in Fuzhou.Analysis results show that the energy consumption of GSHP is 15% less than that of ASHP through all year,where there is 13% less in summer and 20% less in winter.Although the seasonal energy efficiency ratio of GSHP in Fuzhou is higher than that of ASHP,it has no obvious effect on the energy efficiency as it is in the hot summer and cold winter zone.In comparison with ASHP,the GSHP is not cost-effective. 相似文献
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This paper describes the double layer horizontal ground source heat pump systems constructed in 1998 with the buried depth of 0.9 m and 1.8 m. The program of study includes experimental equipments, heat exchanger size, testing meter and methods for data analysis. In addition, the heating and cooling performance at typical days are also illustrated. Among the influencing factors on the performance of the ground source heat pump systems, the parameter of heat exchanger and operation patterns of heat pump systems are analyzed.A heat transfer model has been set up for horizontal heat exchanger. 相似文献
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The air conditioning system using a ground source heat pump(GSHP) combined with a radiant floor integrates the advantages of both types,giving such a system large potential for popularization.After experimenting with one house's hybrid system,the design processes and construction methods for such a system can be summarized.In the experiment,different terminal devices were used to adopt varying winter and summer climatic conditions.It is suggested that the constructors should make good use of resources and waste water during the construction phase.The experimental results show that this hybrid system runs steadily and it supports a better temperature field to meet the requirement for the human comfort.Finally,a hybrid system managment strategy is suggested. 相似文献
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Energy consumption of water intake is one of the key factors for energy saving in the application of the open loop surface water heat pump system. An energy efficiency ratio coupling model for open loop surface water source heat pump systems was established on the basis of the energy consumption model for the water intake and the heat pump units. According to energy saving rate and regulation of energy consumption of water intake, dynamic temperature limits of water intake in different water supply temperature of cooling tower and different pump head were proposed so as to find a calculation method of temperature limits of water intake of open loop surface water heat pumps. Moreover, the energy saving rate of surface water source heat pump systems compared with traditional air conditioning systems under various condition was also calculated. 相似文献
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CUI Wen-zhi~ 《保鲜与加工》2004,(11):88-91
A new kind of evaporative heat transfer experiment for the cooling process of condensers is conducted. The test coil is immersed in an air-water bubbling layer. The air-water two-phase flow passes through the heating tubes of the coil. Due to the motion of the air bubbles in the water, a thin water film forms on the surface of the heating tubes. As the air bubbles passing by the tubes the water is evaporated into the air. The tubes of coil reject heat to the water film, and the evaporation of the water film then rejects heat to the air bubble stream. This heat transfer mode significantly increases the heat transfer coefficient between tubes and air. The consumption of the power of a water pump can be decreased. Moreover, the airflow rate required is less than that of an air-cooled condenser.The pressure drop of air through air-water bubbling layer and the heat transfer between the tubes and water are experimentally investigated in the paper. The results show that the factors affecting the pressure drop and the heat transfer coefficient involve the pore geometry of sieve plate, the height of the air-water bubbling layer, the air flow rate through the sieve plate and the heat flux of tubes. The heat transfer coefficient between tube and water is two times larger than that of falling film of water on the outer surface of tube. 相似文献
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水源热泵在温室加温中的应用研究 总被引：16，自引：1，他引：15
采用多层覆盖、减小直接加热空间的温室节能设计措施,设计建造了试验温室,在水源热泵热风加温条件下,对试验温室的温度、空气相对湿度、水源热泵的实际制热系数进行了测定,对试验温室采用水源热泵加温的节能效果进行了评价,结果表明：夜间水源热泵加温条件下,温室东西方向的水平温度分布均匀,南北相距12m的水平方向上存在着0.9℃的温差,中部距地面2.2m的垂直空间上平均存在1℃的温差,24:00—08:00,空气相对湿度低于80%;试验用水源热泵实际热系数为3.31。与燃煤锅炉热水加温的玻璃温室相比,试验温室采用水源热泵加温相对节能46.5%,直接加温成本较燃煤锅炉加温高82.2%,经计算,当试验温室与对照玻璃温室面积相等时,采用水源热泵加温可相对节能69.1%,直接加温成本仅较燃煤锅炉加温的玻璃温室高5.8%。 相似文献
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Influence of Backfill Air Gap on Soil Temperature Recovery in Ground coupled Heat Pumps 总被引：2，自引：0，他引：2
Air gap may easily emerge in the progress of backfill in ground heat exchange due to field operation problems. The single U tube three dimensional numerical heat transfer model is set up and there are 3 kinds of backfill air gap assumptions for computational analysis, which are the most common situations in practical projects. Different air gap situations will have considerable effects on soil heat transfer, especially the factor of soil temperature recovery performance, which is investigated in this research, and there is practical project operating data for the comparison confirmation with the theoretical calculation results in inlet and outlet water temperatures. It can be concluded that the backfill air gap will increase the soil average excess temperature in the period of recovery inside the place where the air gap is, and degrade the heat transfer performance of the ground heat exchange. 相似文献
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苏北地区日光温室能量分配动态研究 总被引：1，自引：1，他引：0
为了进一步提高日光温室保温性能,减轻温室内低温寡照灾害发生,以苏北（徐州）番茄日光温室为研究对象,利用采集的2010年12月-2011年4月温室小气候数据及番茄发育数据,根据日光温室小气候形成的物理过程与机理,系统研究了冬春季节不同天气类型及不同叶面积指数对温室能量分配的影响。结果表明：日光温室内潜热、显热随着室内总辐射量的改变而发生变化,阴天以显热消耗为主,潜热消耗量全天低于显热;晴天日光温室内用于作物蒸腾的能量显著多于阴天,阴天室内外贯流传热消耗的能量远远多于晴天;随着叶面积指数增大,到达地面的太阳辐射减少,地面升温慢,室内空气与地表的显热交换量减少,同时室内空气与墙体的显热交换增加。本研究结果可为温室的结构优化及冬春季节日光温室管理提供科学依据。 相似文献