重复压裂气井产能模拟研究

Simulation Study on Productivity of Refractured Gas Wells

由于重复压裂气井原有裂缝的失效程度难以评价,导致重复压裂气井的产能预测常常有很大的误差。为此,根据重复压裂气井的压前产量和含水率,拟合了原有裂缝的有效率,在考虑新裂缝和原有裂缝共同作用的情况下,建立了气、水两相平面二维的裂缝-油藏数学模型,通过对模型的数值求解,对重复压裂气井进行了产能评价。研究表明,在考虑新、老裂缝共同作用下的产能评价方法,能更为准确地预测重复压裂后的生产动态情况,对压裂时机的确定、压后经济效益的预测都具有重要的指导意义。

It is difficult to evaluate the failure extent of previous fractures in refractured gas wells, which results in a big error in productivity prediction. In order to solve the problem, the validity of previous fractures is matched based on the pre-fracturing yield and water cut data, and a 2D model with water-gas two phases is established to account for the effects of both previous and new fractures. By numerical calculation, the productivity of refractured gas well is estimated. According to the analyses of results derived from the model, the production performance is more precise and the model offers a better guideline for the determination of fracturing initiation and prediction of post-fracturing economic benefits.