Uniform Gradient Element Formulation with Hourglass Control Scheme for Solving Fully Coupled Finite-Element Equations for Saturated Soils

In fluid flow and heat transfer, the finite element based fully coupling solution for all conservation equations is cost effective for most of the two dimensional, isothermal problems, but suffers in the storage and solution efficiency for large three dimensional problems. The segregated solution algorithm has been designed to address large scale simulation with avoiding the direct formulation of a global matrix. There is trade-off between performing a large number of less expensive iterations by segregated solvers compared to less number of more expensive fully coupled solvers. In this paper, a Finite Element based scheme based on preconditioned GMRES coupled algorithm and SUPG (Streamline Upwind Petrov-Galerkin) pressure prediction/correction segregated formulations have been discussed to solve the steady Navier-Stokes equations. A systematic comparison and benchmark between the segregated and fully coupled formulation has been presented to evaluate the individual benefits and strengths of the coupling and segregated procedure by studying lid-driven cavity problem and large industry application problem with respect to the system storage and solution convergence.

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Total Hourglass Control - A Robust Finite Element Formulation for the Calculation of Organ Deformations

Computer Methods in Biomechanics & Biomedical Engineering ◽

10.1080/10255840108908004 ◽

2001 ◽

Vol 4 (3) ◽

pp. 189-208

Author(s):

ROLAND HUTTER ◽

PETER NTEDERER∗

Keyword(s):

Finite Element ◽

Finite Element Formulation ◽

Element Formulation ◽

Hourglass Control

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Study on Key Factors of Numerical Simulation on Automotive Panel Forming

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.503-504.115 ◽

2012 ◽

Vol 503-504 ◽

pp. 115-118

Author(s):

Qiang Wang

Keyword(s):

Numerical Simulation ◽

Finite Element ◽

Adaptive Mesh ◽

Material Model ◽

Element Formulation ◽

Key Factors ◽

Shell Elements ◽

Automobile Panel ◽

Hourglass Control ◽

Element Type

In this paper, for improving simulative accuracy of auto panel forming, some key factors of numerical simulation with finite element method on automobile panel stamping forming are researched. These key factors include finite element algorithm, adaptive mesh, element type and element formulation, hourglass control, material model, and so on. Through simulation example and analysis show that the dynamic explicit algorithm is suitable for metal stamping forming and the static implicit algorithm for springback stage, the adaptive mesh must be adopted in sheet blank forming, element should be selected shell elements, material model should be selected Barlat’s 3-parameter plasticity model.

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Fully coupled finite element model for dynamics of partially saturated soils

Soil Dynamics and Earthquake Engineering ◽

10.1016/j.soildyn.2009.03.002 ◽

2009 ◽

Vol 29 (9) ◽

pp. 1294-1304 ◽

Cited By ~ 14

Author(s):

Nadarajah Ravichandran

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Element Model ◽

Saturated Soils ◽

Partially Saturated ◽

Partially Saturated Soils ◽

Fully Coupled

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Dynamics of Branched Pipeline Systems Conveying Internal Unsteady Flow

Journal of Vibration and Acoustics ◽

10.1115/1.2893937 ◽

1999 ◽

Vol 121 (1) ◽

pp. 114-122 ◽

Cited By ~ 22

Author(s):

Usik Lee ◽

Joohong Kim

Keyword(s):

Finite Element ◽

Equations Of Motion ◽

Fluid Pressure ◽

Finite Element Formulation ◽

Dynamic Equations ◽

Pipeline System ◽

Element Formulation ◽

Nonlinear Coupling ◽

Coupling Terms ◽

Fully Coupled

The pipeline system conveying high pressurized unsteady internal flow may experience severe transient vibrations due to the fluid-pipe interaction under the time-varying conditions imposed by the pump and valve operations. In the present work, a set of fully coupled dynamic equations of motion for the pipeline system are developed to include the effect of the circumferential strain due to the internal fluid pressure. A finite element formulation for the fully coupled dynamic equations of motion is introduced and applied to several sample pipeline systems. The connectivity conditions for both fluid and structural variables at the junction of a branched pipeline system are properly incorporated in the finite element formulation. To ensure the validity and accuracy of the present theory of pipedynamics, the same pipeline system considered in a reference work is revisited and the present numerical results are compared with those given in the reference work. A series pipeline system with high reservoir head is then analyzed to investigate the effect of the additional linear/nonlinear coupling terms in the present pipedynamic theory. Numerical tests show that the nonlinear coupling terms may become significant at high fluid pressure and velocity.

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Finite Element Formulation for Static Shape Control of a Thin Euler-Bernoulli Beam Using Piezoelectric Actuators

Aerospace ◽

10.1115/imece2004-60117 ◽

2004 ◽

Cited By ~ 2

Author(s):

Eric J. Ruggiero ◽

John Singler ◽

John A. Burns ◽

Daniel J. Inman

Keyword(s):

Finite Element ◽

Active Control ◽

Shape Control ◽

High Surface ◽

Weak Form ◽

Element Formulation ◽

Bernoulli Beam ◽

Control Scheme ◽

Surface Precision ◽

Euler Bernoulli Beam

The main component of future space satellites will be an ultra-large, ultra-low mass aperture for high bandwidth communication or high quality imaging from on-orbit. Such an aperture will require an extremely high surface precision tolerance in order to be effective, especially for imaging purposes. Such tight surface precision tolerances dictate the use of an active control scheme to enable tight control of the shape of the aperture. Further, by integrating an active control scheme during the fabrication process, the aperture will become multi-functional and enable many scientific endeavors. One possible method for analyzing ultra-flexible space structures is through the use of the finite element method. Although many commercial packages are available, careful design of a tailored finite element solver can reveal important information about the system, such as where sensors should be placed on the structure. As an illustrative example, this work formulates the weak form of the equation of motion governing the dynamics of a cantilevered, Euler-Bernoulli beam. In particular, static shape control will be implemented on such a beam using a mathematically formulated LQR controller.

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