异常温压复合地层注热流体井井筒传热计算

Heat conduction research of well injected hot liquid under compound strata of abnormal temperature and pressure

考虑到储层温度、压力对于注热开采井井筒热损失的重要性,利用热量传递基本理论和能量守恒原理,建立了含有异常温压储层的注热流体井井筒热损失计算模型。分析了地温梯度和地层压力系数对岩石热物性参数的影响,计算了不同流体注入速率和不同隔热层参数下的井筒热损失程度,并讨论了地层温度压力对井筒流体稳定时间和稳定温度的影响。结果表明,对于单一的砂质沉积,地层压力系数越高,岩石的导热系数越大,热扩散系数越小;温度异常对井筒热损失影响较为明显,存在高温、低压地层的井筒热损失小,井筒流体到达稳定状态时温度较高。该模型可用于现场同类油藏的井筒沿程温度预测。

Considering the importance of strata temperature and pressure on wellbore heat loss,we established a computational model of thermal losses of well injected hot liquid under the compound strata of abnormal temperature and pressure based on the theory of energy conservation and heat transfer.We analyzed the impacts of geothermal gradient and pressure coefficient on the thermal properties of layers and calculated the thermal losses of wellbore of different injection rate and different properties of thermal-protective coating under different stratum condition of temperature and pressure.We also discussed the impacts of stratum temperature and pressure on the stabilization time and stabilization temperature of wellbore liquid.The obtained results show that the reservoir with a higher pressure coefficient will produce larger heat conduction coefficient and smaller heat diffusion factor.The influence of abnormal temperature condition on heat loss is more obvious.The wellbore heat loss with a high-temperature or low-pressure stratum is low,but the stabilization temperature is high.The model could be used in the temperature prediction of wellbore in the similar reservoirs.