摘要
利用Fluent软件构建闭式中深层井下换热数值模型,研究内管绝热性和绝热段长度对换热性能的影响,结果表明:内管绝热性对深井换热性能的影响显著,当内管导热系数在低于0.12 W/(m·K)范围内减小时,出口温度及每延米换热量近似为线性增大;内管分段绝热可在保证换热效果的前提下有效减小内管绝热段长度,且对于不同井深,合理绝热比例均为0.875,绝热比例为0.875与全段绝热相比,出口温度和每延米换热量的变化量分别不超过0.48%和0.63%。
A numerical model of the closed loop deep downhole heat exchanger(DHE)was built based on Fluent software.The influence of insulation capacity of the central pipe and the length of insulation section on the heat exchange performance were researched.Results show that insulation of the central pipe has a significant influence on the heat exchange performance.When the conductivity of the central pipe decreases below 0.12 W/(m·K),the outlet temperature and heat transfer rate shows rise trend linearly.It is proved that the segmented insulation is an effective method to reduce the length of insulating central pipe without influence on the heat transfor performance.There existing an optimum ratio of the central pipe at 0.875 for a wide range of well depth.To be more specific,compared with whole length insulated central pipe,the outlet temperature and heat transfer rate vary less than 0.48%and 0.63%respectively.
作者
李思奇
赵军
李扬
马凌
王珺瑶
王诗贺
Li Siqi;Zhao Jun;Li Yang;Ma Ling;Wang Junyao;Wang Shihe(Key Laboratory of Efficient Utilization of Low and Medium Grade Energy,MOE,Tianjin University,Tianjin 300350,China)
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2020年第11期369-374,共6页
Acta Energiae Solaris Sinica
基金
天津市重点研发计划(17YFZCGX00580)
天津市建委科技项目(2017-8)。
关键词
地热能
换热器
闭式循环系统
井下
分段绝热
geothermal energy
heat exchangers
closed loop systems
downhole
segmented insulation
