埋地热油管道稳定运行条件下热力影响区的确定

Determination of the thermal influence zone of buried hot oil pipeline on steady operation

建立了埋地热油管道热力影响区的数学模型 ,并用有限元法进行了求解。在此基础上 ,对地温、管内油温、管道直径、管道埋深和土壤导热系数等参数与管道水平方向热力影响范围的关系进行了定量分析 ,分别计算了直径为 4 2 6 ,72 0mm的管道在地温为 2 2 ,15 ,8℃条件下水平方向的热力影响范围。结果表明 ,在其他条件相同时 ,地温越低、管道直径越大或者油温越高 ,管道水平方向热力影响范围越大。在热油管道通常的埋深范围 (1.2～ 1.8m)内 ,埋深变化时 ,水平方向热力影响范围差别不大。计算结果与现场实测结果吻合 。

A mathematical model for determining the thermal influence zone of buried hot oil pipeline was developed and solved numerically by the finite element method. Based on the model,the effect of soil temperature surrounding pipeline,oil temperature,pipe diameter, buried depth of pipe and heat conductivity coefficient of soil on the thermal influence distance in the horizontal direction of pipeline was analyzed quantitatively. The horizontal thermal influence distances of buried pipelines with the diameters of 426 mm and 720 mm at 22℃,15 ℃ and 8℃were determined respectively. Compared with other factors,the pipe buried depth variation in the commonly adopted range from 1.2 to 1.8 meters leads to little difference in the horizontal thermal influence distance. The calculated results agree well with the field-measured data. The rationality of the model was verified.