Numerical Investigation of Downhole Perforation Pressure for a Deepwater Well

Abstract

During the production of deepwater wells, downhole perforation safety is one of the key technical problems. The perforation fluctuating pressure is an important factor in assessing the wellbore safety threat. Due to difficulty in describing the downhole perforation pressure by using the existing empirical correlations, a prediction model based on data fitting of a large number of numerical simulations has been proposed. Firstly, a numerical model is set up to obtain the dynamic data of downhole perforation, and the exponential attenuation model of perforation pressure in the wellbore is established. Secondly, a large number of numerical simulations have been carried out through orthogonal test design. The results reveal that the downhole perforation pressure is logarithmic to the total charge quantity, increases linearly to the wellbore initial pressure, shows an exponential relationship with downhole effective volume for perforation, and has a power relationship with the thickness of casing and cement as well as formation elastic modulus. Thirdly, the prediction of perforation peak pressure at different positions along the wellbore agrees well with the field measurement within a 10% error. Finally, the results of this study have been applied in the field case, and an optimization scheme for deepwater downhole perforation safety has been put forward.

Scientific justification of the perforation methods for Famennian deposits in the southeast of the Perm Region based on geomechanical modelling

“…However, these works cover only certain aspects of modelling these types of perforation. In [32,33], the problem of column deformation when making cumulative holes is considered, and there is no analysis of stresses in the reservoir rock. In publication [34], sand removal was modelled when making a perforation hole based on a discrete model.…”

“…This software implements the ratios describing poroelastic behaviour of a porous medium, and it is successfully used to solve geomechanical problems when developing hydrocarbon fields [36,37]. The software has shown itself well in numerical calculations of geomechanical modelling problems [33,38,39], especially when considering the complex geometry of slotted and perforated holes [32,40].…”