Productivity Prediction Method of 3D Seepage Horizontal Wells in Heterogeneity Gas Reservoir

The productivity prediction mathematical model of 3D seepage horizontal wells in heterogeneity gas reservoir is established and also quantitatively calculated by means of finite element method.The permeability and other gas reservoirs parameters of the different space in the geological model is spread to the grid in the corresponding position of the finite element model,which represents the heterogeneity in the 3D gas reservoir.The effect of the heterogeneity on the productivity of the horizontal wells in gas reservior is analysized. The result shows that the reservoir heterogeneity plays an important role in gas productivity production from horizontal wells,and the gas production of horizontal wells with high permeability channels is obviously higher than the horizontal wells which in homogeneous gas reservoir under the condition of the same drawdown pressure.The more number of the high permeability and the bigger the permeability,the smaller the pressure consumption,and the higher the horizontal output.Eventually,according to the geological characteristics and the reservoir features of a deep gas field located in Songliao Basin,an example on productivity prediction of horizontal wells in this gas field is presented.Study presented in this paper is accordant with the practical situation,providing an effective approach to predict productivity of horizontal wells in gas reservoir,especially in anisotropic gas reservoir.