摘要
建立地埋管传热过程的二维稳态模型,分制冷和供热2种工况,考虑周围土壤温度、回填材料、管径、管材、管内介质的流量和进出口温差等参数的影响。采用适用于薄体的边界元法计算地埋管传热问题,根据计算结果比较不同管壁厚度情况下竖直地埋管的换热差异,为地埋管的设计和运行指标提供定量分析依据。进一步分析不同管材对U型竖直地埋管换热量的影响,并计算两种工况下竖直管道所需的埋设长度。边界元法分析U型等地埋管传热问题,使用较少的单元数可获得较精确的结果,尤其是对该文中管壁薄体和土壤厚体的耦合问题。
A two-dimension steady-state heat transfer model about the buried pipe was established based on the reasonable simplification. The influence of the main parameters of the buried pipe system , such as soil temperature, flux and temperature difference of the medium between inlet and outlet of the pipe, as well as diameter dimension, wall thickness and material of the pipe on the heat transfer efficiency was considered. The heat transfer between the buried pipes and ground source subjected to two cases of cooling and heating was analyzed by a special boundary element method （BEM） which was able to deal with the thin body. Then the heat transfer performance of the vertical buried pipe with respect to its heat transfer coefficient, diameter dimension and wall thickness were discussed according to the computed results. Furthermore, the heat transfer capacity of the single U-type vertical buried pipe was evaluated by the BEM so that the vertical lengths of the buried pipe related to the two cases were obtained. The BEM uses very less number of elements and achieves more accurate results in evaluating the heat transfer of the buried pipes in comparison with the FEM. Especially, the BEM is able to solve the coupling problems of both thin and thick bodies.
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2015年第4期936-942,共7页
Acta Energiae Solaris Sinica
基金
国家自然科学基金(11272111
11102056)
关键词
地源热泵
地埋管
传热
边界元法
薄体
ground source heat pump
buried pipe
heat transfer
boundary element method
thin body
