Discussions on numerical accuracy of the vector finite element methods using the vector-shape function

This paper presents a realistic and fast method of simulating ballscrew drives, taking into account the position-dependent changes in dynamics as the nut moves along the ballscrew. It achieves this by first using a strategy whereby the motion of the nut along the ballscrew is accurately and smoothly captured in simulations using the shape function of the finite element model as an interpolating function. Secondly, it applies a method based on Component Mode Synthesis with Modal Acceleration Recovery to achieve a full reduction of the ballscrew while still allowing the nut to move from node to node on the ballscrew. As a result the computational efficiency of the model is improved significantly without any considerable sacrifice of its accuracy.

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Study on Finite Dynamic Element Method for Dynamic Consolidation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.261-263.567 ◽

2004 ◽

Vol 261-263 ◽

pp. 567-572

Author(s):

Xiu Guang Song ◽

Xiu Yuan Ma ◽

Jin Zhang Liu

Keyword(s):

Finite Element ◽

Finite Element Methods ◽

Dynamic Characteristics ◽

Shape Function ◽

Vibration Characteristics ◽

Practical Calculation ◽

Dynamic Consolidation ◽

Dynamic Shape ◽

Dynamic Element ◽

Element Method

Based on the conception of dynamic shape function, a finite dynamic element method (DEM) is developed for the computation of dynamic consolidation. Formulae of the DEM are also derived. This method overcomes the shortcomings of conventional finite element methods, i.e., the vibration characteristics of the soil to be consolidated cannot be considered. Therefore, it practically reflects the dynamic characteristics of consolidation. The programs for the DEM are also written. Results of practical calculation show that the method is correct and feasible.

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Equilibrium Profile of Modern Belted Radial Ply Tires: Its Determination and Performance Benefits

Tire Science and Technology ◽

10.2346/tire.13.410203 ◽

2013 ◽

Vol 41 (2) ◽

pp. 127-151

Author(s):

Rudolf F. Bauer

Keyword(s):

Finite Element ◽

Aspect Ratio ◽

Finite Element Methods ◽

Mathematical Analysis ◽

Internal Stresses ◽

Stress Concentrations ◽

Equilibrium Profiles ◽

Equilibrium Profile ◽

And Performance ◽

Beneficial Property

ABSTRACT The benefits of a tire's equilibrium profile have been suggested by several authors in the published literature, and mathematical procedures were developed that represented well the behavior of bias ply tires. However, for modern belted radial ply tires, and particularly those with a lower aspect ratio, the tire constructions are much more complicated and pose new problems for a mathematical analysis. Solutions to these problems are presented in this paper, and for a modern radial touring tire the equilibrium profile was calculated together with the mold profile to produce such tires. Some construction modifications were then applied to these tires to render their profiles “nonequilibrium.” Finite element methods were used to analyze for stress concentrations and deformations within all tires that did or did not conform to equilibrium profiles. Finally, tires were built and tested to verify the predictions of these analyses. From the analysis of internal stresses and deformations on inflation and loading and from the actual tire tests, the superior durability of tires with an equilibrium profile was established, and hence it is concluded that an equilibrium profile is a beneficial property of modern belted radial ply tires.

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