关键词: 分支, 水平井, 曲线, 拉氏变换, 试井, 分析

Abstract: The transient pressure analysis and morden well testing interpretation methods for multi branched horizontal wells in anisotropic formation are developed.The wellbore storage constant and the skin factor are taken into consideration.First,to use rotation of axes derive instantaneous soures functions of a linear section source which has arbitrary angle relative to x axis in xy plane.The instantaneous source function G xy of N linear sections,whose extend lines all pass origin of coordinates,are given by means of superposition.And vertical z direction source functions Gz for three cases i.e.formation top and bottom are prescribed flux,prescribed pressure and mixed boundarise in anisotropic formation are given also.The Green's functions G(x,y,z,t)=Gxy^*Gz of general multi branched horizontal wells are obtained by Newman's product method.Then the analytic expressions of dimensionless pressure PD(w) and well bottom pressure PD(w) in Laplace space are given.Finally,in Laplace space the dimensionless well bottom pressure PWD(C_D,S,s),which has taken into account the dimensionless wellbore storage C_D and the skin factor S,are obtained.Here the s is the Laplace transform variable.The expression of P_WD include PD(w) only as well as the constant C_D and S.We make use of numerical inversion of Lapalace transforms to give a set of type curves.At certain conditions the above mentioned results are also appliable for single horizontal well in wedge shaped fault.

Key words: branch, horizontal well, curve, Laplace transform, well testing, analysis