致密气藏大型加砂压裂气井产能预测研究

Research on Productivity Forecasting for Gas Well With Big Scale Sand Fracturing to Condense Gas Reservoir

在Gringarten等人提出无限导流垂直裂缝模型解的基础上,通过对产生的裂缝进行微元段划分,结合均匀流率垂直裂缝模型,得出了裂缝微元段数为200时的井底不稳定流动压力的半解析解,根据杜哈美原理和二项式计算产能的方法,结合气井生产,提出拟合井底压力的方法,得到一种专门针对无限导流垂直裂缝模型的多产量测试产能预测模型。通过该模型计算新场气田上沙溪庙组气藏大型加砂压裂井的产能,将计算结果与实际测试值进行对比,结果较为可靠,证明了该方法的可行性。

Based on solution to vertical crack model of infinite flow present by Gringartens and by classifying micro-sections for produced cracks and integrating with vertical crack model of uniform flow rate, half analytic solution to unstable flow pressure at bore bottom for 200 numbers of micro-sections of cracks is derived. According to Duhamei theory and method of binominal calculating productivity and combing with production of gas well, bore hole pressure is suggested so that a forecasting model for testing productivity with multiple productions has been gained specially for vertical crack model of infinite flow. Calculating production potential of big scale sand fracturing well in up Shaxi-Temple gas reservoir in Xinchang gas field by this model and comparing the calculated results with actual testing value, the result is reliable which proves this method is feasible.