Hydraulic Fracture Optimization with a p-3D Mode in multi layers reservoir

About 10 years ago was introduced the concept of Unified Fracture Design (UFD) as a coherent way to size the fracture geometry for the expressed purpose to physically optimize the well performance. We used the proppant Number as a correlating parameter, which in turn provided the maximum dimensionless productivity index (JD) which corresponds to the optimum dimensionless fracture conductivity, CfD. Once the latter is determined, the fracture dimensionless, fracture length and width are set. If one assumes the fracture height is known and constant then the calculation is simple and 2D fracture propagation model can be used. However, fracture height is not constant throughout the fracture and it cannot be considered constant during execution, depending greatly on the net pressure and vice versa. We are presenting here an iterative procedure where the fracture height is related to the net pressure. In the procedure, for any assumed net pressure, the fracture height, along with the mass of proppant and the permeabilities of the reservoir and the proppant, lead to the Proppant Number which in turn determines the desire length and width. A fracture propagation model, such as PKN geometry for lateral growth, coupled whit a changing fracture height, leads to the calculation of the net pressure which is compared with the one assumed. Convergence of the assumed and calculated net pressure is what is sought.Also, in this paper we contributed an algorithm for designing a pseudo 3D model. In addition, we point the importance of the p-3D in a large array of reservoirs.

Keywords:

Unified Fracture Design , KGD , optimum fracture design , and pseudo-3D