共查询到18条相似文献,搜索用时 359 毫秒
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青岛蓝色硅谷区域地质构造特殊,地热资源丰富。目前该区域地热资源的勘查程度较低,地热资源利用形式单一,优质地热资源浪费严重。本文采用岩土热响应测试法对蓝色硅谷区域内的地埋管测试孔的岩土热物性进行了现场测试,利用48 h的测试数据,采用线热源模型进行数据分析,得到土壤导热系数为2.278 W/(m∙K)。同时,采用柱热源模型模拟夏季工况,得到的流体温度变化趋势与实验工况相同,且进、出水温度分别为35.1℃和30.4℃,与实验工况下的35.1℃及30.8℃吻合较好。该研究可用于指导土壤源热泵的热物性分析以及青岛蓝色硅谷地热资源综合开发。 相似文献
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利用现有土壤源热泵实验台测定了岩土热物性参数,采用传热学反问题的方法对实验数据进行分析。测试过程中从岩土取热,U型地埋管换热器形成一个线热汇,使其在测试过程中与热泵实际运行时的工作状态相接近,测试更准确,节省测量过程的耗电量。以每个采样时刻作为计算节点,取平均值作为计算结果。测定结果显示岩土导热系数为3.2W/(m·K),回填材料导热系数为2.0W/(m·K),岩土热扩散率为0.85×10~(-6)m~2/s。可靠性分析表明:其标准误差分别为0.08W/(m·K),0.04W/(m·K)和0.039×10~(-6) m~2/s。 相似文献
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利用地层热物性原位测试技术测得的地层热物性参数的精度要高于土壤类别辨识法或瞬态测量的探针法,更适于地源热泵系统埋管换热器的长度的设计。结合大广高速公路双辽服务区的地层热物性参数的测试情况对地层热物性原位测试的过程及施工注意事项进行简介。 相似文献
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岩土导热系数是地源热泵地埋管换热器的重要设计参数;测井单位深度换热量是地埋管换热器系统的设计依据。掌握工程区域岩土的热物性及换热性能,是保证地源热泵系统高效、稳定运行的关键。文章建立了现场测试岩土导热系数及换热量的方法,并结合沈阳浑南高新技术产业开发区某地源热泵工程,测试分析了岩土导热系数和测井单位深度换热量。结果表明,该区域的岩土具有较好的导热能力,适合采用地埋管地源热泵系统;在特殊地理条件下设计地源热泵系统方案前,应对拟建区域的地质条件进行全面勘探,以优选工程区域,为岩土热响应测试结果的可靠性提供保障。 相似文献
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提出一种新型的能源桩换热管型式,即深层埋管式能源桩。利用Comsol Multiphysics建立三维方法模拟桩体-土体传热,一维方法模拟管内水动态传热传质的数值模型,考虑了土体温度随深度的变化,模拟出口水温随时间的变化规律并计算换热量,比较深层埋管式与传统的1-U型、1-W型能源桩的换热量,分析了桩径、桩体导热系数、桩体密度、桩体比热容等不同参数对新型深层埋管式能源桩换热量的影响。模拟结果表明:以运行50 h为例,深层埋管式的总体换热量比1-U型、1-W型分别高122%、54%;而对于单位管长换热量,深层埋管式比1-U型、1-W型分别高9%、50%,桩径从0.5 m增加到1 m,换热量增加14.3%;桩体导热系数从1.2 W/(m∙K) 增大至2.5 W/(m∙K),换热量增加9.6%;桩体密度从1 800 kg/m3增大到2 600 kg/m3,换热量增大0.8%;桩体比热容从637 J/(kg∙K) 增大到1 037 J/(kg∙K),换热量增大1.1%。因此深层埋管式的热性能优于传统1-U型和1-W型,在满足能源桩力学性能的前提下,为了提高深层埋管式能源桩换热性能,可以适当增大桩径。对于桩体材料的选择,应该选择导热系数较高的材料。密度和比热容对换热量的提升影响不大。 相似文献
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Technology directed at geothermal energy, one of our renewable energy sources, to heat and air-condition buildings has become very attractive in recent years following the significant developments in ground-source heat pump (GSHP) systems. In general, although the energy efficiency of GSHP systems is far superior to conventional air-source heat pump (ASHP) systems, GSHP system is still expensive. Therefore, GSHP system employs the foundation pile of buildings as heat exchanger is introduced in order to reduce the initial cost. When designing a GSHP system (especially in case of the energy pile system), it is necessary to accurately predict the heat extraction and injection rates of the heat exchanger. The thermal and hydraulic properties of the ground are very important to accurately predict heat transfer between the ground heat exchanger and the ground. In particular, those are the most important design parameters because energy pile system is installed only a few tens of meters deep. In this paper, an estimation method is suggested in order to determine the thermal and hydraulic properties of the ground for design the heat exchanger of energy pile system base on geotechnical investigation for the design the building's foundations. The use of results from generally applied geotechnical site investigation methods to estimate ground thermal and hydraulic properties was evaluated. 相似文献
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For optimum design of borehole thermal energy storage (BTES) and ground sources heat pump (GSHP) applications, determination of underground thermal properties is required. The design and economic feasibility (number and depth of boreholes) of these systems need thermal conductivity of geological structure, λ (W m?1 K?1), and thermal resistance of ground heat exchanger, R (K W?1 m). Thermal properties measured in laboratory experiments do not coincide with data of in situ conditions. Therefore, in situ thermal response test equipment has been developed and used in Canada, England, Germany, Norway, U.K., U.S.A. and Sweden to ensure precise designing of BTES systems. This paper describes the results and evaluations of the Adana continual thermal response test measurements. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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热除菌利用细菌在高温下失活的原理,是一种安全、有效、环保的杀菌方法。将热杀菌技术与Trombe墙结合,提出一种热除菌型Trombe墙系统,能同时实现建筑室内采暖和热杀菌功能。围绕提出的除菌型Trombe墙进行墙体热性能实验研究,探究墙体全天的热性能;同时建立系统传热热传质模型,进行室内典型细菌的热失活分析。结果表明,在环境温度为18.1℃、太阳辐射强度为620.6 W/m2的实验条件下,日均空气热效率为0.46;对于大肠杆菌、利斯特氏菌、植物乳杆菌、山夫顿堡沙门氏菌和酿酒酵母五种细菌,热除菌产生的洁净空气量在0 ~ 40 m3/h范围内,全天净空气总产生量分别为94.01 m3/(m2∙d)、86.51 m3/(m2∙d)、100.70 m3/(m2∙d)、94.95 m3/(m2∙d) 和100.10 m3/(m2∙d);当换气次数为0.5 h-1、细菌从室外进入室内的穿透系数为0.8、室外平均细菌浓度为447.10 CFU/m3时,室内五种细菌的除菌率分别为95.03%、91.54%、95.49%、95.22%、95.48%。 相似文献
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Permeability and thermal conductivity test units were set up to study the heat and mass transfer performance of the host material, i.e. expanded natural graphite (ENG), for consolidated activated carbon (AC) adsorbent. The permeability was tested with nitrogen as the gas source, and the thermal conductivity was studied using steady-state heat source method. The results showed that the values of permeability and thermal conductivity were 10-15 to 10-12 m2 and 1.7 to 3.2 W/(m·K), respectively, while the density compressed expanded natural graphite (CENG) varied from 100 to 500 kg/m3. The permeability decreased with the increasing density of CENG, whereas the thermal conductivity increased with the increasing density of CENG. Then the thermal conductivity and permeability of granular AC were researched. It was discovered that the thermal conductivity of samples with different grain size almost kept constant at 0.36 W/(m·K) while the density was approximately 600 kg/m3. This means that the thermal conductivity was not related to the grain size of AC. The thermal conductivity of CENG was improved by 5 to 10 times compared with that of granular AC. Such a result showed that CENG was a promising host material for AC to improve the heat transfer performance, while the mass transfer performance should be considered in different conditions for utilization of adsorbent. 相似文献