各向异性油藏水平井产量公式校正方法研究

RESEARCH ON CORRECTION METHODS FOR HORIZONTAL WELL PRODUCTIVITY FORMULA IN ANISOTROPIC RESERVOIRS

为了精确计算各向异性油藏中水平井的产量,对比研究了5种非均质油藏水平井产量公式的各向异性校正方法,对现有校正方法中存在的问题进行了探讨。对油藏渗透率分别进行了算术平均、几何平均和调和平均处理,结果表明,经以上3种方法处理后的水平井产量依次减小,即几何平均和调和平均处理比算术平均处理更能体现各向异性对水平井产量的影响。根据陈氏公式的校正方法推导出了新的Joshi各向异性校正公式,其结果与陈氏公式计算结果具有较好的一致性。通过实例计算,研究了油藏各向异性等因素对水平井产量的影响,表明各向异性对水平井产量影响显著。

For the sake of calculating horizontal well productivity in anisotropic reservoirs accurately,five kinds of anisotropic correction methods for horizontal well productivity formula are analyzed and some problems of existing correction methods discussed.By expressing permeability as the forms of arithmetic mean,geometric mean and harmonic mean,the productivity of horizontal wells decreases in turn,i.e.,geometric mean and harmonic mean correction can show the influence of permeability heterogeneity on the productivity of horizontal wells better than arithmetic mean correction.Based on the correction method of Chen′s formula,a new Joshi′s anisotropic correction formula is derived,and the result is in accordance with the one from Chen′s.Case study indicates that the anisotropy has a great influence on productivity of horizontal wells.