水平井变质量流动压降规律实验研究

水平井由于壁面孔眼流体的流入,造成沿水平井筒为流量不断增加的变质量流动。通过室内模拟实验,采用螺旋射孔钢管为实验管材,对壁面孔眼入流对主流压降的影响进行了研究。研究结果表明：随着注入比的增加,管中压降增大;由于入流与主流的掺混,将会造成一定附加压降,该值的大小与加速度压降和注入比两者间的比值成线性关系。考虑不同注入比条件,建立了井筒流动压降新模型,井筒中流动总压降为射孔管摩阻压降与附加压降两者之和,模型计算结果平均相对误差仅为7.5%,精度高于其他理论模型,从而为井筒流动和油藏流动耦合计算提供理论支持。

Experimental study for pressure drop of variable mass flow in horizontal well

The flow in the horizontal well is the variable mass flow due to the inflow through the perforated holes.Pressure drop due to inflow was measured in a horizontal perforated pipe loop by using water as working fluids.The experiment result shows that pressure drop grows as a result of increasing injection ratio.The mixture of inflow and main flow can cause the additional pressure drop.Moreover,the additional pressure drop has linear relationship with the ratio of acceleration pressure drop and injection ratio.A new model of pressure gradients for the vary mass flow in perforated pipes was developed.The total pressure drop consists of two parts including perforated pipe wall friction loss and additional loss.The predictive values by new model is in good agreement with true values,the average relative error is 7.5%.The accuracy of the model proposed in this paper is better than other models.So the new model can be used in coupled well and reservoir simulation model.