Coupling equivalent plate and finite element formulations in multiple-method structural analysis

In this paper, the finite element analysis for stress/deformation/modes of vibration for the centrifugal fan impeller with constant thickness backward-curved blades using CATIA software will be presented. The principal steps of the finite element analysis procedure using CATIA/Generative Structural Analysis environment will be presented: creating the 3D model; configuring the mesh; applying the restraints; applying the loads; running the numerical static analysis and the numerical frequency analysis; interpreting the results and observing the modes of vibration correlating with the impeller mode shape. This procedure will be used for 4 different centrifugal fan impellers according with the 4 blade design methods and the results will be comparatively analyzed. For each design method, two materials will be used: steel with density of 7860 kg/m3 and aluminium with density of 2710 kg/m3. Two important results have been obtained after the structural analysis: under the working conditions considered for the analysis, all 4 blade design methods leads to impellers with very good mechanical behaviour; any frequency of the main modes of vibrations for all blade design methods and for both materials is not in phase with the impeller speed, thus the possibility of resonance being eliminated.

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Performance of the Incremental and Non-Incremental Finite Element Formulations in Flexible Multibody Problems

Journal of Mechanical Design ◽

10.1115/1.1289636 ◽

1999 ◽

Vol 122 (4) ◽

pp. 498-507 ◽

Cited By ~ 35

Author(s):

Marcello Campanelli ◽

Marcello Berzeri ◽

Ahmed A. Shabana

Keyword(s):

Finite Element ◽

Multibody Systems ◽

Absolute Nodal Coordinate Formulation ◽

Flexible Multibody Systems ◽

Large Displacement ◽

Body Motion ◽

Absolute Nodal Coordinate ◽

Flexible Multibody ◽

The Absolute ◽

Finite Element Formulations

Many flexible multibody applications are characterized by high inertia forces and motion discontinuities. Because of these characteristics, problems can be encountered when large displacement finite element formulations are used in the simulation of flexible multibody systems. In this investigation, the performance of two different large displacement finite element formulations in the analysis of flexible multibody systems is investigated. These are the incremental corotational procedure proposed in an earlier article (Rankin, C. C., and Brogan, F. A., 1986, ASME J. Pressure Vessel Technol., 108, pp. 165–174) and the non-incremental absolute nodal coordinate formulation recently proposed (Shabana, A. A., 1998, Dynamics of Multibody Systems, 2nd ed., Cambridge University Press, Cambridge). It is demonstrated in this investigation that the limitation resulting from the use of the infinitesmal nodal rotations in the incremental corotational procedure can lead to simulation problems even when simple flexible multibody applications are considered. The absolute nodal coordinate formulation, on the other hand, does not employ infinitesimal or finite rotation coordinates and leads to a constant mass matrix. Despite the fact that the absolute nodal coordinate formulation leads to a non-linear expression for the elastic forces, the results presented in this study, surprisingly, demonstrate that such a formulation is efficient in static problems as compared to the incremental corotational procedure. The excellent performance of the absolute nodal coordinate formulation in static and dynamic problems can be attributed to the fact that such a formulation does not employ rotations and leads to exact representation of the rigid body motion of the finite element. [S1050-0472(00)00604-8]

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Parameter-transfer finite element method for structural analysis

AIAA Journal ◽

10.2514/3.11706 ◽

1993 ◽

Vol 31 (5) ◽

pp. 923-929 ◽

Cited By ~ 4

Author(s):

R. Barboni ◽

P. Gaudenzi ◽

A. Mannini

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Structural Analysis ◽

Element Method

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Thermomechanical Analysis of the Welding Process Using the Finite Element Method

Journal of Pressure Vessel Technology ◽

10.1115/1.3454296 ◽

1975 ◽

Vol 97 (3) ◽

pp. 206-213 ◽

Cited By ~ 179

Author(s):

E. Friedman

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Welding Process ◽

Thermomechanical Analysis ◽

Analytical Models ◽

The Finite Element Method ◽

Nonuniform Temperature ◽

Butt Weld ◽

Transverse Bending ◽

Finite Element Formulations

Analytical models are developed for calculating temperatures, stresses and distortions resulting from the welding process. The models are implemented in finite element formulations and applied to a longitudinal butt weld. Nonuniform temperature transients are shown to result in the characteristic transverse bending distortions. Residual stresses are greatest in the weld metal and heat-affected zones, while the accumulated plastic strain is maximum at the interface of these two zones on the underside of the weldment.

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Penalty Method Involving Electric Sliding Contact Problem

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.701-702.246 ◽

2014 ◽

Vol 701-702 ◽

pp. 246-249

Author(s):

Sai Tan ◽

Jun Yong Lu ◽

Xin Lin Long ◽

Xiao Zhang

Keyword(s):

Finite Element ◽

Contact Problem ◽

Physical Quantity ◽

Penalty Method ◽

Sliding Contact ◽

Interface Condition ◽

Calculation Results ◽

Coupled Equation ◽

Finite Element Formulations ◽

Methods Numerical

Basing on governing Maxwell and energy equation of rail gun considering armature movement in two dimension, The total domain to be solved is divided into two subdomains: moving (armature) part and static (rail) part, finite element formulations of two subdomains are built independently, then using the interface condition of two subdomains, formulations are connected by coupled equation which is derived out by penalty method. Shifted physical quantity is used to simulate movement. The final magnetic-thermal coupled fields finite element formulations of rail gun are established by these methods. Numerical calculation results compared by theoretical and other numerical results verify that penalty method is an effective way to deal with electric sliding contact problem associating with Shifted physical quantity method.

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