为了准确预测非凝析气与蒸汽混注水平井的井筒沿程流动特征，基于热采水平井管柱跟端注汽与趾端注汽模式，充分考虑水平井的孔眼出流、压降损失以及注入流体的热效应和相态特征，建立射孔水平井混注非凝析气( N2、CO2)与蒸汽时的井筒沿程变质量流动半解析模型。采用井筒细分微元与节点分析方法进行求解，对气汽混注下的稠油水平井井筒沿程流动特征进行研究，并探讨各注入参数对于井筒流动特征的影响。结果表明：模型的模拟结果显示仅靠近注汽点位置处的井段加热效果较好，这与矿场实际情况较为吻合；相比传统注蒸汽，气汽混注下的水平井热有效长度更长，加热效果更好；不同注汽模式的水平井具有不同的加热效果，在实际生产过程中，可以轮回改变注入管柱的下入深度，实现不同的加热模式，改善水平段油藏加热效果。%In order to accurately predict the performance characteristics of non-condensable gas and steam along a horizontal wellbore, a semi-analytical flow model for the gas and steam mixture was developed based on thermal recovery string with the horizontal well and toe steam injection mode. The influences of various factors were considered, including perforation out-flow, pressure drops, thermal effect and phase behavior of the fluid injected. The model was solved using the methods of wellbore micro-control-element and node analysis. The flowing characteristics of the gas and steam mixture along the horizon-tal well were investigated, and the influences of different injection parameters were discussed. The results indicate that only the well segment near to the injection position can be effectively heated, which is in line with the results of field tests. Com-pared with the conventional steam injection, the injection of the combined gas and steam in horizontal wells has a better heat-ing effect,and different injection methods can have different heating effects. In field operations, it is suggested that the down-hole position of the injection pipe can be changed cycle by cycle in order to improve the heating effect in the reservoir.
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