稠油油藏SAGD蒸汽腔位置综合评估及产量预测

产量和蒸汽腔位置对稠油油藏SAGD开发至关重要，现有的预测模型仅考虑了蒸汽腔的横向扩展，无法预测与相邻井蒸汽腔接触后的产量。针对蒸汽腔横向扩展阶段和向下扩展阶段的不同特征，引入了热穿透深度，修正了流动势函数，建立了抛物线产量预测模型。结果表明，蒸汽腔横向扩展初期产量逐渐增加，而后因蒸汽腔界面倾角减小，产量降低；在蒸汽腔向下扩展阶段，产量进一步下降。对模型分析表明，SAGD更适用于开发油层厚度大的油藏，需要结合油田情况确定最佳井距。抛物线产量预测模型考虑了蒸汽腔向下扩展阶段特征，通过与前人实验数据进行比较，验证了该模型的准确性。

Comprehensive Evaluation on Steam Chamber Location and Production Prediction of SAGD in Heavy Oil Reservoirs

Production and steam chamber location are critical for steam assisted gravity drainage (SAGD) in heavy oil reservoirs. The existing prediction model only considers the lateral expansion of steam chamber and cannot predict the production of adjacent wells after steam chamber contact. According to the different characteristics of the steam chamber in the lateral expansion stage and the downward expansion stage, a parameter of thermal penetration depth was introduced, the flow potential function was modified, and a parabolic production prediction model was established. The results show that the production increases gradually in the initial lateral expansion stage of steam chamber, and then decreases due to the reduction of the inclination of the steam chamber interface; in the downward expansion stage of steam chamber, the production further decreases. The model analysis reveals that SAGD is more suitable for thick reservoir development, and the optimal well spacing needs to be determined depending on the oilfield conditions. The parabolic production prediction model takes the characteristics of the steam chamber into account in the downward expansion stage, and the accuracy of the model is verified by comparing with the previous experimental data.