FINITE ELEMENT METHOD FOR POSTFRACTURING PRODUCTION PERFORMANCE OF WELLS IN LOW_PERMEABILITY RESERVOIR

Some past works,such as the performance prediction of reservoirs containing one or more hydraulic fractures with irregular azimuth,the simulation of three dimensional simulation of propped fractures,analyses on influence of initiation pressure and influence of the phase_seepage flowing curve of fractures,description of irregular boundary,effective simulation of reservoirs with non_horizontal or non_equivalent payzone thickness,the impact of varing fracture conductivity on performance of postfractured wells,are imperfect.A para_parameter finite element method can improve above works.A couple of differential equations for reservoir_fracrure system were established.The finite element theory was used as a discrete method for solving the above equations in apace,while the backward finite difference method was used in time step.The method of IMPIS and preconditioned conjugate gradient method were used to resolve the pressure equations of oil phase and equations of water saturation.On the basis of that,the Visual Basic for Windows language was used to develop the software for resolving above problems.In the meantime,the black oil model was used to verify the calculating results of the software developed in this paper.A field case shows an excellent agreement and indicates that the software developed by authors is reliable and can be put into field application.