Numerical investigation of tubular expansion and swelling elastomers in oil wells

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Sayyad Zahid Qamar
Keyword(s):  
Numerical Simulation ◽  
Performance Evaluation ◽  
Cost Effectiveness ◽  
Contact Pressure ◽  
Material Properties ◽  
Expansion Ratio ◽  
New Developments ◽  
Formation Type ◽  
Sealing Pressure ◽  
Petroleum Drilling

Abstract Solid expandable tubular technology and swelling elastomer seals find extensive use in the repair of aging reservoirs. To improve productivity and cost-effectiveness, they have also become an integral part of new developments such as slim wells and completions with reduced or no cementing. This work reports the use of numerical simulation to investigate the joint use of expandable tubulars and swell packers in various petroleum drilling applications. Material properties of steel tubular and five different swelling elastomers are obtained through mechanical testing. Simulations are performed to study the sealing pressure at the elastomer-formation boundary. Different parameters are studied, such as elastomer material, expansion or compression ratio, seal length, seal thickness, tubular end condition, and formation type. Higher values of rubber elasticity, tubular expansion (expansion ratio), and elastomer compression result in higher seal contact pressure. Contact pressure is higher when the elastomer is pressing against wellbore formation as compared to steel outer casing (zero friction vs. friction), and when the formation is assumed to be rigid as compared to elastic or elastic-plastic. Results of this investigation can be used both for performance evaluation and design enhancement of coupled solid-expandable-tubular and swellable-packer applications.

Numerical Simulation of Contact Pressure Evolution in Fretting

1994 ◽  
Vol 116 (2) ◽  
pp. 247-254 ◽  
Author(s):  
L. Johansson
Keyword(s):  
Numerical Simulation ◽  
Contact Pressure ◽  
Stability Criterion ◽  
Frictional Contact ◽  
Elastic Bodies ◽  
Numerical Instabilities ◽  
Archard’S Law Of Wear ◽  
Pressure Evolution

In the present paper an algorithm for frictional contact between two elastic bodies is presented. The algorithm is applied to the calculation of the evolution of contact pressure between two elastic bodies when material is being removed by fretting. To this end Archard’s law of wear is implemented into the algorithm. It is noticed that the calculated pressures after a period of fretting differ considerably from the initial Hertz type pressures. Further, it is noted that numerical instabilities can occur in explicit type wear calculations, and a stability criterion is suggested.

Simulation Study of Granular Compaction Dynamics under Vertical Tapping

2007 ◽  
Vol 555 ◽  
pp. 107-112 ◽  
Author(s):  
D. Arsenović ◽  
S.B. Vrhovac ◽  
Z.M. Jakšić ◽  
Lj. Budinski-Petković ◽  
A. Belić
Keyword(s):  
Numerical Simulation ◽  
Molecular Dynamics ◽  
Friction Coefficient ◽  
Simulation Study ◽  
Material Properties ◽  
Two Dimensions ◽  
Second Phase ◽  
Hard Disks ◽  
Compaction Process ◽  
Granular Compaction

We study by numerical simulation the compaction dynamics of frictional hard disks in two dimensions, subjected to vertical shaking. Shaking is modeled by a series of vertical expansions of the disk packing, followed by dynamical recompression of the assembly under the action of gravity. The second phase of the shake cycle is based on an efficient event−driven molecular−dynamics algorithm. We analyze the compaction dynamics for various values of friction coefficient and coefficient of normal restitution. We find that the time evolution of the density is described by ρ(t)=ρ∞ − ρEα[−(t/τ)α], where Eα denotes the Mittag−Leffler function of order 0<α<1. The parameter τ is found to decay with tapping intensity Γ according to a power law τ ∝ Γ−γ , where parameter γ is almost independent of the material properties of grains. Also, an expression for the grain mobility during compaction process has been obtained.

scholarly journals A brief compendium of water entry results derived from laboratory tests of various types of wall assemblies

2019 ◽  
Vol 282 ◽  
pp. 02050
Author(s):  
Michael A. Lacasse ◽  
Nathan Van Den Bossche ◽  
Stephanie Van Linden ◽  
Travis V. Moore
Keyword(s):  
Numerical Simulation ◽  
Performance Evaluation ◽  
Laboratory Tests ◽  
Moisture Transfer ◽  
Control Design ◽  
Water Entry ◽  
Building Envelope ◽  
Test Results ◽  
Different Types ◽  
Wood Frame

There is an increase in the use of hygrothermal models to complete the performance evaluation of walls assemblies, either in respect to design of new assembles or the retrofit of existing wall assemblies. To this end there are guides available in which is provided information on moisture loads to wall assemblies. This includes, for example, Criteria for Moisture-Control Design Analysis in Buildings given in ASHRAE 160, Assessment of moisture transfer by numerical simulation provided in EN 15026, and NRC’s “Guidelines for Design for Durability of the Building Envelope”. The designer of a new assembly or evaluator of an existing wall is tasked with having to determine what moisture loads to apply to the wall and where to apply this load within the assembly. Typically there is little or no information that is readily available regarding moisture loads to walls and thus the suggested hourly moisture load, as given in ASHRAE 160, is 1% by weight of the total driving rain load to the wall (i.e. kg/m2-hr). In this paper, a brief compendium of water entry test results derived from laboratory tests of various types of wall assemblies is provided from which estimates of moisture loads to different types of wall can be developed. Water entry test results are given of wood frame walls typically used in housing, but also metal-glass curtain walls and other commercial wall assemblies, where possible, in terms of driving loads to the wall.

The Numerical Simulation of Effective Elastic Response for WC-Co Cemented Carbide

2015 ◽  
Vol 1096 ◽  
pp. 417-421
Author(s):  
Pei Luan Li ◽  
Zi Qian Huang
Keyword(s):  
Numerical Simulation ◽  
Finite Element Method ◽  
Finite Element ◽  
Theoretical Model ◽  
Material Properties ◽  
Cemented Carbide ◽  
Elastic Response ◽  
The Finite Element Method ◽  
Simulation Results ◽  
Element Method

By the use of finite element method, this paper predicts the effects of the shapes of reinforcements with different ductility (Co) on the effective elastic response for WC-Co cemented carbide. This paper conducts a comparative study on the material properties obtained through theoretical model, numerical simulation and experimental observations. Simulation results indicate that the finite element method is more sophisticated than the theoretical prediction.

FEM Simulation of Swelling Elastomer Seals in Downhole Applications

2013 ◽  
Author(s):  
Maaz Akhtar ◽  
Sayyad Zahid Qamar ◽  
Tasneem Pervez ◽  
Farooq Khalfan Al-Jahwari
Keyword(s):  
Contact Pressure ◽  
Oil Recovery ◽  
Compression Ratio ◽  
Saline Water ◽  
Fem Simulation ◽  
Petroleum Exploration ◽  
Water Salinity ◽  
Well Design ◽  
Sealing Pressure ◽  
Water Swelling

Petroleum exploration and development industry is witnessing a rapid growth in the use of swelling elastomers. They are being used in new applications aimed at enhanced oil recovery through slimming of well design, zonal isolation, water shutoff, etc. Initially developed as a problem-solving strategy (for repair of damaged or deteriorating wells), swelling elastomers are now targeting major savings in cost and time through reduction in borehole diameter, reduced casing clearance, cementless completions, etc. Due to material and geometric nonlinearity, modeling and simulation of swelling elastomer applications becomes quite complex. In this work, finite element simulation has been carried out to study swelling elastomer seal performance in downhole petroleum applications using the software ABAQUS. A hyperelastic model (that most closely resembles swelling elastomer behavior) is used for simulation of seal behavior. A series of experiments have been designed and performed to determine necessary material properties of a water-swelling elastomer as it gradually swells when exposed to saline water of two different concentrations at 50°C (to emulate field conditions of medium-depth oil wells). A large number of simulations are carried out to investigate sealing behavior against water salinity and swelling time. Sealing pressure at the contact surface between elastomer and formation (or outer casing) is studied for variations in seal length, seal thickness, compression ratio, water salinity, and swelling period. Results show that seal contact pressure increases with amount of swelling, seal length, and compression ratio; higher salinity environment results in lower sealing pressure; and more contact pressure is generated in the case of rock formation as compared to steel outer casing.

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