Horizontal wells are thought to be necessary in formationsrnwith low-permeability to increase the recovery and reduce thernrisk of drilling a dry hole. The horizontal well may crossrnnatural fissures. Although hydraulically fracturing horizontalrnwells in such formations is a risky job, it may be necessary inrnorder to achieve commercial production. This is especiallyrntrue for naturally fractured gas reservoirs with matrixrnpermeability in microdarcies and where natural-fracturernnetwork does not contribute considerably to the flow from thernreservoir into the wellbore.rnThis study investigates the transient pressure behavior of arnmultiply fractured horizontal well (MFHW), as well as thernlong time performance of such a completion in an anisotropicrnnaturally fractured reservoir of infinite extent.rnCombining boundary element method and Laplacerntransform, single-fracture solution is considered first as itrnconstitutes the core part of the multiple-fracture model. Then,rna solution to multiply fractured horizontal wells is presented,rnwhich assumes fractures of distinct properties, it allows forrnunequal spacing between fractures, and permits the perforationrnof portions of the interval between fractures. Furthermore, itrnallows the juxtaposition of any number of perforated intervalsrnand any number of fractures.rnThe pseudo-steady state is considered to account for thernfluid transfer between the matrix blocks and the fracturernnetwork.rnDue to its simplicity, accuracy, and reliability, proceduresrnfor using the new technique referred to as "Tiab's DirectrnSynthesis" have been developed to analyze the transientrnpressure and pressure derivative behavior of a MFHW in arnnaturally fractured reservoir. Individual fracture properties canrnbe determined if individual flow rate contributions arernmeasured, otherwise an average conductivity and half-lengthrnis determined.
展开▼
