Modeling of Pillowing Stress in Corroded Lap Joints

2011 ◽  
Vol 189-193 ◽  
pp. 2139-2143
Author(s):  
Da Zhao Yu ◽  
Yue Liang Chen ◽  
Yong Gao ◽  
Wen Lin Liu ◽  
Yong Zhang
Keyword(s):  
Mathematical Model ◽  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Lap Joints ◽  
Lap Joint ◽  
Material Loss ◽  
Internal Surfaces ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

Based on chemical composition of the corrosion product, a mathematical model was developed to predict the extent of the pillowing deformation of lap joints of LY12CZ in term of thickness inside the joint. The model can offer the capability for predicting the extent of corrosion within the joint in terms of thickness loss at the internal surfaces of the skins from the amplitude of the pillowing of the outer skin. Three-dimensional finite element model of a bolted joint have been developed in the non-linear finite element code MSC.Marc and attempts were made to validate it by comparing results with the mathematical model. The results show that corrosion pillowing can significantly increase the stress in a lap joint for material loss below the detection limit of current nondestructive inspection techniques, thus increasing the risk of premature cracking. In addition, the analyses show that the locations of maximum stress of lap joint will change with the material loss increases. Simulating the effect of corrosion on lap joint only by reducing the panel thickness will result in neoconservative life estimates if corrosion pillowing is ignored.

An Experimental and Numerical Analysis of Riveted Single Lap Joints

1994 ◽  
Vol 208 (2) ◽  
pp. 79-90 ◽  
Author(s):  
C-P Fung ◽  
J Smart
Keyword(s):  
Finite Element ◽  
Stress Concentration ◽  
Three Dimensional ◽  
Element Model ◽  
Lap Joints ◽  
Published Data ◽  
Single Lap Joints ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element ◽  
Stress Patterns

Countersunk and snap riveted single lap joints have been examined both experimentally and numerically. A total of 11 specimens were fatigued to failure with failures occurring in either the plate or the rive***r. The failures have been metallurgically examined to determine the cause of failure. The joints have also been analysed using the finite element method. Initially a single lap joint has been modelled as a ‘stepped plate’ and the results for the stress concentration factor found to be in reasonable agreement with published data. However, the stress concentration for this joint occurred at a point away from the point of failure of a riveted joint. A fuller three-dimensional finite element model has been constructed and the stress patterns around the rivet determined. These stress patterns are discussed in relation to the results from the metallurgical examination.

Three-Dimensional Analyses of Single Rivet-Row Lap Joints — Part II: Elastic-Plastic Response

1999 ◽  
Author(s):  
K. Iyer ◽  
C. A. Rubin ◽  
G. T. Hahn
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Lap Joints ◽  
Finite Element Analyses ◽  
Lap Joint ◽  
Stress Concentrations ◽  
Elastic Plastic ◽  
Linear Elastic ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

Abstract Three-dimensional finite element analyses of an elastic-plastic, single rivet-row, aluminum lap joint are presented and compared with previous results for linear elastic models. The calculations treat non-countersunk aluminum and steel rivets, 3 different configurations of countersunk rivets as well as two values of the friction coefficient. The compliance of the connection, rivet tilt, the stresses in the panels, peak plastic strains and the contact pressures and slip amplitudes at the rivet-panel and panel-panel interfaces are evaluated. The transverse, axial, and shear stress distributions and the stress concentrations generated in four different rivets are derived from the linear elastic models and related to the rivet geometry. Laboratory measurements of the lap joint compliance and local out-of-plane displacements that support the reliability of the finite element analyses are presented.

Hysteretic damping characteristics of a mechanical tensioner: Modeling and experimental investigation

2018 ◽  
Vol 233 (7) ◽  
pp. 1890-1902 ◽  
Author(s):  
Hao Zhu ◽  
Yumei Hu ◽  
Yangjun Pi ◽  
Weidong Zhu
Keyword(s):  
Mathematical Model ◽  
Finite Element ◽  
Finite Element Model ◽  
Three Dimensional ◽  
Element Model ◽  
Damping Characteristics ◽  
Hysteretic Damping ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element ◽  
The Mathematical Model

The aim of this article is to investigate hysteretic damping characteristics of a typical tensioner used in engine accessory drive systems. An experiment device is developed to measure the friction coefficients of three contact pairs within the tensioner. Statistic results of test data show that the friction coefficient is linearly dependent on normal forces, and thus a linear function is used to describe it. An exact mathematical model and an accurate three-dimensional finite element model are proposed in this study to calculate the relationship of friction torque and rotation angle as well as the damping characteristics of the tensioner. The mathematical model and three-dimensional finite element model are verified through an experiment. Comparison indicates that both the mathematical and finite element model can accurately predict the working torque of the tensioner during operation process, while the finite element model has better accuracy in predicting the damping characteristics than the mathematical model.

Finite Element Analysis of Nonuniformity of Tires with Imperfections5

2007 ◽  
Vol 35 (3) ◽  
pp. 226-238 ◽  
Author(s):  
K. M. Jeong ◽  
K. W. Kim ◽  
H. G. Beom ◽  
J. U. Park
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Three Dimensional ◽  
Element Model ◽  
Radial Force ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Dimensional Finite Element ◽  
Force Variation ◽  
Three Dimensional Finite Element

Abstract The effects of variations in stiffness and geometry on the nonuniformity of tires are investigated by using the finite element analysis. In order to evaluate tire uniformity, a three-dimensional finite element model of the tire with imperfections is developed. This paper considers how imperfections, such as variations in stiffness or geometry and run-out, contribute to detrimental effects on tire nonuniformity. It is found that the radial force variation of a tire with imperfections depends strongly on the geometrical variations of the tire.

Mechanical Simulation of Knee Movement in Basketball Shooting

2013 ◽  
Vol 336-338 ◽  
pp. 760-763
Author(s):  
Hui Yue
Keyword(s):  
Finite Element ◽  
Cruciate Ligament ◽  
Three Dimensional ◽  
Element Model ◽  
Basketball Player ◽  
Knee Movement ◽  
Dimensional Finite Element ◽  
Anterior Cruciate ◽  
Three Dimensional Finite Element

A short explanation of the finite element method as a powerful tool for mathematical modeling is provided, and an application using constitutive modeling of the behavior of ligaments is introduced. Few possible explanations of the role of water in ligament function are extracted from two dimensional finite element models of a classical ligament. The modeling is extended to a three dimensional finite element model for the human anterior cruciate ligament. Simulation of ligament force in pitching motion of basketball player is studied in this paper.

Sign in / Sign up

Export Citation Format

Share Document