水平井蒸汽吞吐加热半径和地层参数计算模型

Calculating models for heating radius of cyclic steam stimulation and formation parameters in horizontal well after soaking

蒸汽吞吐水平井加热半径和焖井后地层温度和压力的计算是水平井产能评价和动态预测的基础。由于蒸汽沿着水平段流动有摩擦损失,因而蒸汽的压力、温度和干度沿着水平段的分布是不均匀的。根据水平井变质量流和传热学原理,基于质量守恒、动量定理和能量守恒及镜像反映和势叠加原理,建立了水平井蒸汽吞吐加热半径和焖井后温度压力计算模型。以某油藏参数为基础,对该模型计算结果与数值模拟结果进行的比较发现,二者基本吻合,从而验证了模型的正确性。

The calculations of heating radius and the pressure and temperature of formation in horizontal well during cyclic steam stimulation after soaking are the bases for the evaluation of productivity and forecast of dynamic performance of horizontal well. The distribution of steam pressure, temperature and quality along the horizontal sections of wellbore are uneven, because of friction loss of steam. The new calculation models for heating radius and distribution of pressure and temperature in horizontal well after soaking were established on the basis of the variable-mass flow theory and the principle of heat conduction by the use of mass conservation theorem, momentum theorem and energy conservation theorem. The calculation result of the new model is in good agreement with that of the numerical simulation for the same parameters from the same reservoir.