化工学报2019，Vol.70Issue(5)：1750-1760,11.DOI:10.11949/j.issn.0438-1157.20181470
并联双U形桩基埋管换热器热-力学特征的数值仿真研究
Exploration on thermo-mechanical characteristics of energy piles with double-U pipes buried in parallel by means of numerical simulations
摘要
Abstract
Pile-based borehole heat exchangers (energy piles) can be used as terminal heat transfer devices for ground source heat pumps, playing the role of conventional pile foundations at the same time. Thus, not only their heat transfer performances must be good enough to meet heating or cooling air conditioning demands, but also the stress changes caused by intermittent heat extraction and release alternatively from and to the soil surroundings should not endanger the stability of building structures above. To reveal the thermo-mechanical characteristics of energy piles sufficiently, the software of Comsol and Abaqus were implemented jointly to establish a three-dimensional dynamic numerical simulation model for an energy pile with double-U pipes buried in parallel. Simulation results were validated by the data obtained during an in-situ test. Dynamic temperature distributions inside pile body, axial force distributions and the displacement of the pile body were analyzed. The heat transfer performances and mechanical characteristics of four energy piles in different ratios of pile length-to-diameter with double-U pipes buried in parallel were studied under the conditions of different water flow rates, as well as those of energy piles with three different forms of buried pipes. The results show that the influence of the form of the buried pipes and that of the length-to-diameter ratio of the pile on their heat transfer and mechanical performance are significant, and the influence of the flow velocity is weak. The larger the length-diameter ratio and the flow velocity, the greater the heat transfer capacity, the larger the temperature difference between the inlet and outlet water. And the additional pile axial forces, pile top displacements and side frictional resistances caused by temperature changes increase as well accordingly.关键词
计算流体力学/热力学/传热/实验验证/数值模拟Key words
computational fluid dynamics/thermodynamics/heat transfer/experimental verification/numerical simulation分类
建筑与水利引用本文复制引用
张爽,赵蕾,高林,刘华..并联双U形桩基埋管换热器热-力学特征的数值仿真研究[J].化工学报,2019,70(5):1750-1760,11.基金项目
国家自然科学基金项目(51878535) （51878535）
国家科技部科技支撑计划项目(2014BAJ01B01) （2014BAJ01B01）
