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Title: Evaluation of flow characteristics of perforations including nonlinear effects with the finite-element method

Abstract

This study presents results of finite-element modeling of steady-state flow in perforated natural completions. Use of a mesh chosen carefully by grid sensitivity analysis permits evaluation of flow with more precision than that achieved by previous investigators. Also, for the first time, flow characteristics of perforated completions are evaluated with the non-Darcy effect resulting form converging flow around the perforation taken into account. The results indicate confirmation of Locke's results qualitatively but 5 to 10% overprediction by the nomograph, the importance of angular phasing between adjacent perforations, the uncertainty in generally accepted severe permeability impairment in the compacted zone, and a significant reduction in productivity owing to a non-Darcy effect around the perforation for high-rate gas wells.

Authors:
Publication Date:
Research Org.:
Schlumberger Perforating and Testing Center
OSTI Identifier:
6776458
Alternate Identifier(s):
OSTI ID: 6776458
Resource Type:
Journal Article
Resource Relation:
Journal Name: SPE (Society of Petroleum Engineers) Product. Eng.; (United States); Journal Volume: 2:2
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; 03 NATURAL GAS; NATURAL GAS WELLS; FLOW MODELS; PERFORATION; STEADY FLOW; OIL WELLS; ACCURACY; DATA COVARIANCES; FINITE ELEMENT METHOD; INCIDENCE ANGLE; NOMOGRAMS; NONLINEAR PROBLEMS; PERMEABILITY; PRODUCTION; SENSITIVITY ANALYSIS; STEADY-STATE CONDITIONS; WELL COMPLETION; DIAGRAMS; FLUID FLOW; MATHEMATICAL MODELS; NUMERICAL SOLUTION; WELLS 020300* -- Petroleum-- Drilling & Production; 030300 -- Natural Gas-- Drilling, Production, & Processing

Citation Formats

Tariq, S.M. Evaluation of flow characteristics of perforations including nonlinear effects with the finite-element method. United States: N. p., 1987. Web. doi:10.2118/12781-PA.
Tariq, S.M. Evaluation of flow characteristics of perforations including nonlinear effects with the finite-element method. United States. doi:10.2118/12781-PA.
Tariq, S.M. Fri . "Evaluation of flow characteristics of perforations including nonlinear effects with the finite-element method". United States. doi:10.2118/12781-PA.
@article{osti_6776458,
title = {Evaluation of flow characteristics of perforations including nonlinear effects with the finite-element method},
author = {Tariq, S.M.},
abstractNote = {This study presents results of finite-element modeling of steady-state flow in perforated natural completions. Use of a mesh chosen carefully by grid sensitivity analysis permits evaluation of flow with more precision than that achieved by previous investigators. Also, for the first time, flow characteristics of perforated completions are evaluated with the non-Darcy effect resulting form converging flow around the perforation taken into account. The results indicate confirmation of Locke's results qualitatively but 5 to 10% overprediction by the nomograph, the importance of angular phasing between adjacent perforations, the uncertainty in generally accepted severe permeability impairment in the compacted zone, and a significant reduction in productivity owing to a non-Darcy effect around the perforation for high-rate gas wells.},
doi = {10.2118/12781-PA},
journal = {SPE (Society of Petroleum Engineers) Product. Eng.; (United States)},
number = ,
volume = 2:2,
place = {United States},
year = {Fri May 01 00:00:00 EDT 1987},
month = {Fri May 01 00:00:00 EDT 1987}
}
  • This study presents results of finite element modelling of steady-state flow in perforated natural completions. Use of a carefully chosen mesh based on grid sensitivity analysis permits evaluation of flow with more precision than achieved by previous investigators. Also, for the first time, evaluation of flow characterstics of perforated completion is made taking into account the non-Darcy effect due to converging flow around the perforation. The results indicate: (1) confirmation of Locke's findings qualitatively but 5-10% overprediction by the nomograph (2) importance of angular phasing between adjacent perforations, (3) untenability of generally accepted severe permeability impairment in the compacted zone,more » and (4) significant reduction in productivity due to non-Darcy effect around the perforation for high-rate wells.« less
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  • In Part 1 of this paper, Gurson`s mixed hardening plasticity model with strain and stress-controlled nucleations, was used in large deformation finite element program to study the plastic flow and damage in the uniaxial compression of cylinders under sticking friction. Due to low stress triaxiality at the bulge of the cylinders, it was found that localization may occur before void coalescence. In this paper, necessary conditions of localizations are analyzed for the axial compression of porous cylinders under sticking friction. Shear band type of localization with a normal mode of fracture has been predicted for the majority of the casesmore » studied. Various existing localization conditions and fracture criteria are assessed using the results form the simulation. The maximum shear stress at failure is approximately constant and a constant critical damage can not be found.« less