Parametric study of controllable parameters in fracture-based wellbore strengthening

Fracture-based wellbore strengthening techniques have been widely used in the oil industry to reduce the cost of lost circulation, especially in depleted reservoirs. Accurate prediction of induced-fracture geometry is of critical importance for best particle size distribution (PSD) selection of wellbore strengthening materials (WSM). Conventional parametric analyses mainly focused on rock properties, well conditions and WSM plug location. Thus, the deficiency of ignoring time and fluid dynamics may result in erroneous operations. In this paper, a dynamic fracture model based on the dislocation method is employed to qualitatively characterize the influence of controllable parameters on fracture propagation and fracture reopening pressure (FROP). Fracture propagation length and profile are obtained for each parameter with different values. It is found that fluid injection rate, fluid viscosity, fluid injection time, wellbore inclination and wellbore radius have an inverse relationship with FROP. On the other hand, fracture plug width has a positive relationship with FROP. Finally, a procedure for determining optimal wellbore strengthening operations by manipulating the controllable parameters is developed based on the dynamic fracture model. (C) 2017 Elsevier B.V. All rights reserved