摘要
结合北方邯郸地区,通过Fluent软件建立中深层地热能井下同轴套管式换热器换热模型,模拟研究了岩土导热系数、内管导热系数、循环流体流量、循环流体入口温度变化对井下同轴套管式换热器换热性能的影响。结果表明:岩土的导热系数从1 W/(m·K)增加到9 W/(m·K),换热器换热量增长约324.53%;内管导热系数从0.5 W/(m·K)增加到4.5 W/(m·K),换热器换热量减少约40.37%;循环流体流量从10 m^(3)/h增加到50 m^(3)/h,换热器换热量增长约103.92%;循环流体入口温度从5℃增加到15℃,换热器换热量减少约23.14%。所以在实际工程中,应在岩土导热系数相对较大的地域开发中深层地热能,选择导热系数较小的内管以及循环流量较大的井下换热器,并保持外管循环流体入口温度较低。
Taking Handan area in northern China as an example,a downhole coaxial heat exchanger(DCHE) model was established by Fluent software for the mid-deep geothermal energy wells,and the effects of thermal conductivities of soil and inner pipes,the flow rate and inlet temperature of circulating fluid on the heat transfer performance of DCHE were simulated. The results show that as the thermal conductivity of soils and rocks increases from 1 W/(m·K) to 9 W/(m·K),the heat transfer volume of the heat exchanger increases about 324. 53%;as the thermal conductivity of inner pipes increases from 0. 5 W/(m·K) to 4. 5 W/(m·K),the heat transfer volume of the heat exchanger decreases about 40. 37%;as the circulating fluid flow increases from 10 m^(3)/h to 50 m^(3)/h,the heat transfer volume of the heat exchanger increases about 103. 92%;and as the circulating fluid inlet temperature increases from 5 ℃to 15 ℃,the heat transfer volume of the heat exchanger decreases about 23. 14%. Therefore,middle-deep geothermal energy should be developed in areas with relatively large geotechnical thermal conductivity,choosing inner pipe with small thermal conductivity and downhole heat exchangers with large circulating flow,and keeping the circulating fluid inlet temperature in outer pipes low.
作者
袁安冬
唐文龙
汪丽娟
王海涛
YUAN Andong;TANG Wenlong;WANG Lijuan;WANG Haitao(School of Environment and Energy Engineering,Anhui Jianzhu University,Hefei 230601,China)
出处
《安徽建筑大学学报》
2022年第4期61-65,78,共6页
Journal of Anhui Jianzhu University
基金
安徽省重点研究与开发计划项目(202004a07020019,202004a07020049)。
关键词
FLUENT
中深层地热能
换热性能
换热量
fluent
middle and deep geothermal energy
heat transfer performance
heat exchange volume