Popis: |
This paper present to predict the effect of diameter and length of perforation, inflow angle of perforation, inflow velocity and shape of perforation on pressure drop and then productivity index of vertical wellbore with two perforations. In this study, a Computational Fluid Dynamics (CFD) software code ANSYS CFX15.0 has been used to simulate a model of 3-D turbulent flow with stander k−∈ in a perforated vertical wellbore. The simulation for the vertical wellbore is performed by applying the laws of conservation of mass and momentum. The effect of perforation diameter and length of perforation, inflow angle, inflow types of inlet velocity to the perforation and inflow velocity for 180o and two perforations is studied. From the results of this study, the friction pressure drop is a major component of the total pressure drop and the maximum static (friction) pressure drop occurs at the location of perforation and increases with increasing the perforation diameter. For all the perforation diameter with constant length (0.15 m), the friction pressure drop is higher than 82% of the total pressure, the acceleration pressure drop is less than 16% of the pressure drop for both numerical and theoretical results. The mixing pressure drop is about 2% of the total pressure drop for the numerical results. The increase of inflow to main flow rate ratio increasing the total pressure drop and then decreasing in productivity index. |