干热岩生产井温度场的热力计算

Calculation of Temperature Field for Hot Dry Rock Production Wells

为了研究干热岩生产井产液的保温增效问题,根据北京市某生产井井身结构特点,建立了井筒传热计算模型,利用计算流体力学(computational fluid dynamics,CFD)软件对该生产井探测数据进行了核实,并在此基础上提出了对干热岩生产井产液温度场影响因素的分析.结果表明:生产井三开段底部产水源的产液温度最高,热储量大,可使井口出口温度由333.1 K提高到342.3 K;同等工程参数下,泵管下入深度增加到400 m时,可使产液井口出口温度提高到337.6 K,且下入深度越大,产液出口温度越高;产液产速越大,生产时间越少,减少了产液热能损失,产液出口温度变大;相同泵管深度条件下,保温材料泵管产液出口温度比常规材料泵管高出2 K,可提高生产效益.

To study the thermal efficiency of hot dry rock production wells producing fluid,according to the structural characteristics of the well depth of a Beijing production wells, the wellbore heat transfer calculation model was established, which verified the geothermal well detection data by using computational fluid dynamics（ CFD ） software. And on the basis of above research,the analysis of the factors was proposed which affect production well fluid temperature field. Results show that the temperature of the water produced at the bottom of the production well three open section is highest of all, and the heat storage capacity of the water is very big,which makes the outlet temperature of the wellhead increases from 333. 1 K to 342. 3K ; under the same engineering parameters,w h e n the depth increases to 400 m,it makes the wellhead outlet temperature increase to 337. 6 K,and the deeper the depth is,the higher the outlet temperature of the liquid producing will b e ; as improve produced fluid production rate, the shorter production time and heat loss, the larger outlet temperature of liquid producing; under the same condition pump pipe depth,outlet temperature of the liquid producing for heat preservation material pump pipe is 2 K higher than convention pumppipe material,which improve the production efficiency.