层状热储大体积单井循环换热循环动力设备扬程模拟计算

Simulation and calculation of head of circulation power equipment for large volume single well circulation heat exchange in layered heat storage

本文以国内外现有裂隙热储和层状热储循环换热模型为基础,提出一种适用于河北平原馆陶组层状热储非稳定隔水层空间大体积单井循环换热取热不取水技术。该技术利用封隔器将热储段以隔水层为界分为上下两层,中间下入保温管,下抽上灌,顶端为井下换热器,以软水为换热介质,通过换热器换取地热流体中热量,达到取热不取水的目的。以河北东部平原地热井为例,按照黄金分割比例配置保温管外径,根据管材结构、流体流速、黏性系数、运动黏度等确定雷诺数,绘制莫迪图,划分流体状态,选择沿程阻力系数经验公式,模拟地热流体沿程水头损失、局部水头损失、水头提升值和动能水头,确定循环动力设备扬程。同时发现,局部水头损失为沿程阻力水头损失的0.23%~0.44%,水头损失以沿程阻力水头损失为主;当循环流量分别为30 m^(3)/h和50 m^(3)/h时,扬程分别为121.631 m和168.191 m。

Based on the existing heat transfer models of fractured and stratified heat reservoirs at home and abroad,this paper proposes a single well circulation heat transfer technology without water transfer that is suitable for the stable stratified heat reservoir in Guantao Formation in Hebei Plain.The technology uses the packer to divide the heat storage section into upper and lower layers with the waterproof layer as the boundary.In the middle,the insulation pipe is put down,and the upper layer is pumped.The top is the underground heat exchanger,and the soft water is the heat exchange medium.Geothermal wells in the eastern part of the Hebei Plain as an example,according to the golden section proportion configuration insulation pipe diameter,according to the pipe structure,fluid velocity,viscosity coefficient,kinematic viscosity to determine the Reynolds Number,draw the Moody Figure,division of fluid state,select on-way resistance coefficient of empirical formula,the simulation of geothermal fluid frictional head loss,the local head loss,appreciation and kinetic energy head,determine the cycle power equipment head.At the same time,it is found that the local head loss is 0.23%-0.44%of the drag head loss along the path,and the main head loss is the drag head loss along the path.When the circulating flow rate is 30 m^(3)/h and 50 m^(3)/h,the head is 121.631 m and 168.191 m,respectively.