Generalized Inflow Performance Relationship (IPR) for Horizontal Wells

Abstract The horizontal well technology can solve different problems of production from tight formations where conventional technology fails. The aim of this study is to develop a generalized IPR for an oil reservoir in which a well is drilled horizontally. A reservoir simulator is used to simulate the production through this well to construct the IPR curves. A simulation matrix is designed by changing well geometry, well position and rock properties. The IPR data obtained from the numerical simulations are fitted to a Vogel-type relationship and the values of the coefficient, b, are calculated corresponding to different conditions. Consequently, a statistical analysis method is used to determine which factors in the simulation matrix have a significant effect on the value of b. The results show that the only significant factor is the vertical to horizontal permeability ratio of the reservoir. Using the Vogel-type IPR and the correlation for b obtained from statistical analysis in terms of the vertical to horizontal permeability ratio, an IPR suitable for horizontal well productivity is developed taking into account the reservoir and well parameters. In this relationship, the factor b is a function of the vertical to horizontal permeability ratio. The new model is tested against random simulations that are not included in the original simulation matrix for the model development, and better agreement is observed compared to the predictions of previous IPR's available in the literature.