Optimization of the Wrist Pin End of an Automobile Engine Connecting Rod With an Interference Fit

1990 ◽  
Vol 112 (3) ◽  
pp. 406-412 ◽  
Author(s):  
Vijay Sarihan ◽  
Ji Oh Song
Keyword(s):  
Finite Element ◽  
Optimum Design ◽  
Three Dimensional ◽  
Stress Singularity ◽  
Design Strategy ◽  
Structural Components ◽  
Connecting Rod ◽  
Fem Model ◽  
Automobile Engine ◽  
Interference Fit

Current design procedures for complicated three-dimensional structural components with component interactions may not necessarily result in optimum designs. The wrist pin end design of the connecting rod with an interference fit is governed by the stress singularity in the region where the wrist pin breaks contact with the connecting rod. Similar problems occur in a wide variety of structural components which involve interference fits. For a better understanding of the problems associated with obtaining optimum designs for this important class of structural interaction only the design problems associated with the wrist pin end of the rod are addressed in this study. This paper demonstrates a procedure for designing a functional and minimum weight wrist pin end of an automobile engine connecting rod with an interference fit wrist pin. Current procedures for Finite Element Method (FEM) model generation in complicated three-dimensional components are very time consuming especially in the presence of stress singularities. Furthermore the iterative nature of the design process makes the process of developing an optimum design very expensive. This design procedure uses a generic modeler to generate the FEM model based on the values of the design variables. It uses the NASTRAN finite element program for structural analysis. A stress concentration factor approach is used to obtain realistic stresses in the region of the stress singularity. For optimization, the approximate optimization strategy in the COPES/CONMIN program is used to generate an approximate design surface, determine the design sensitivities for constrained function minimization and obtain the optimum design. This proposed design strategy is fully automated and requires only an initial design to generate the optimum design. It does not require analysis code modifications to compute the design sensitivities and requires very few costly NASTRAN analyses. The connecting rod design problem was solved as an eight design variable problem with five constraints. A weight reduction of nearly 27 percent was achieved over an existing design and required only thirteen NASTRAN analyses. It is felt that this design strategy can be effectively used in an engineering environment to generate optimum designs of complicated three-dimensional components.

Finite Element Analysis of Stress Singularities in Attached Flip Chip Packages

2000 ◽  
Vol 122 (4) ◽  
pp. 301-305 ◽  
Author(s):  
A. Q. Xu ◽  
H. F. Nied
Keyword(s):  
Contact Angle ◽  
Finite Element ◽  
Glass Fiber ◽  
Flip Chip ◽  
Three Dimensional ◽  
Stress Singularity ◽  
Local Stress ◽  
Stress Singularities ◽  
Element Analysis ◽  
Three Dimensional Finite Element

Cracking and delamination at the interfaces of different materials in plastic IC packages is a well-known failure mechanism. The investigation of local stress behavior, including characterization of stress singularities, is an important problem in predicting and preventing crack initiation and propagation. In this study, a three-dimensional finite element procedure is used to compute the strength of stress singularities at various three-dimensional corners in a typical Flip-Chip assembled Chip-on-Board (FCOB) package. It is found that the stress singularities at the three-dimensional corners are always more severe than those at the corresponding two-dimensional edges, which suggests that they are more likely to be the potential delamination sites. Furthermore, it is demonstrated that the stress singularity at the upper silicon die/epoxy fillet edge can be completely eliminated by an appropriate choice in geometry. A weak stress singularity at the FR4 board/epoxy edge is shown to exist, with a stronger singularity located at the internal die/epoxy corner. The influence of the epoxy contact angle and the FR4 glass fiber orientation on stress state is also investigated. A general result is that the strength of the stress singularity increases with increased epoxy contact angle. In addition, it is shown that the stress singularity effect can be minimized by choosing an appropriate orientation between the glass fiber in the FR4 board and the silicon die. Based on these results, several guidelines for minimizing edge stresses in IC packages are presented. [S1043-7398(00)00904-X]

Three-Dimensional FEM Simulation of the Ship-Bridge Collision

2013 ◽  
Vol 405-408 ◽  
pp. 3243-3247
Author(s):  
Wei Su ◽  
Ying Sun ◽  
Shi Qing Huang ◽  
Ren Huai Liu
Keyword(s):  
Finite Element ◽  
Boundary Conditions ◽  
Reference Values ◽  
Large Scale ◽  
Three Dimensional ◽  
Fem Simulation ◽  
Structural Safety ◽  
Fem Model ◽  
Finite Element Software

In this paper, the structural safety of the Niuwan Bridge subjected to vessel collision is investigated by the large-scale commercial finite element software ANSYS. A whole FEM model is built and a reasonable analysis and illustration for taking the value of vessel-collision forces is presented. Additionally, under the premise of reasonable simulation of the boundary conditions, the effects of the support abutments, the prestress and the carloads are considered. The analysis results have certain reference values for the anti-collision and reinforcement of bridges.

Three-Dimensional Finite Element Prediction of Machining-Induced Stresses

Manufacturing ◽  
2003 ◽  
Author(s):  
T. D. Marusich ◽  
S. Usui ◽  
R. J. McDaniel
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Metal Cutting ◽  
Three Dimensional ◽  
Constitutive Models ◽  
Fatigue Loading ◽  
Cyclic Fatigue ◽  
Fem Model ◽  
Machined Parts ◽  
Three Dimensional Finite Element

Controlling residual stress in machined workpiece surfaces is necessary in situations where service requirements subject structural members to cyclic fatigue loading. It is desirable to have a predictive capability when attempting to optimize machined parts for cost while taking into account residual stress considerations. One such method of machining modeling is application of the finite element method (FEM). A three-dimensional FEM model is presented which includes fully adaptive unstructured mesh generation, tight thermo-mechanically coupling, deformable tool-chip-workpiece contact, interfacial heat transfer across the tool-chip boundary, momentum effects at high speeds and constitutive models appropriate for high strain rate, finite deformation analyses. The FEM model is applied to nose turning operations with stationary tools. To substantiate the efficacy of numerical and constitutive formulations used, metal cutting tests are performed, residual stress profiles collected, and validation comparison is made.

Three-dimensional elastoplastic finite element and elastohydrodynamic analyses of journal bearings

1997 ◽  
Vol 211 (2) ◽  
pp. 143-152 ◽  
Author(s):  
H Bahai ◽  
H Xu
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Hydrodynamic Pressure ◽  
Cyclic Stress ◽  
Hoop Strain ◽  
Interference Fit ◽  
Lining Material ◽  
Von Mises ◽  
Fourier Type ◽  
Hoop Stresses

It is generally believed that cracks initiating from the surface of bearings with their line perpendicular to the circumferential direction of the shell are predominantly induced by the presence of cyclic hoop stresses in the bearing. A method is proposed in this paper where an elastohydrodynamic (EHD) analysis is combined with a full elastoplastic finite element (FE) stress analysis using a particular Fourier type of element which enables the application of non-uniform, non-axisymmetric hydrodynamic pressure loading to an axisymmetric bearing geometry. The analysis accounts for the effect of the initial interference fit and the three-dimensional pressure distribution which is obtained from the EHD analysis. Plasticity is incorporated into the analysis using the von Mises yield surface hardening rule. The analysis predicts the variation of cyclic stress and strain values in the lining material across the bearing width. It is seen from the analysis that a hoop strain variation changing from tensile in the loaded condition to compressive in the unloaded condition is responsible for the initiation of cracks at the surface of the bearing lining material.

Finite Element Modeling of Hard Roller Burnishing: An Analysis on the Effects of Process Parameters Upon Surface Finish and Residual Stresses

2007 ◽  
Vol 129 (4) ◽  
pp. 705-716 ◽  
Author(s):  
Partchapol Sartkulvanich ◽  
Taylan Altan ◽  
Francisco Jasso ◽  
Ciro Rodriguez
Keyword(s):  
Finite Element ◽  
Residual Stresses ◽  
Process Parameters ◽  
Surface Finish ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Cost Effective ◽  
Machined Surface ◽  
Fem Model ◽  
Roller Burnishing

Hard roller burnishing is a cost-effective finishing and surface enhancement process where a ceramic ball rolls on the machined surface to flatten the roughness peaks. The ball is supported and lubricated by hydrostatic fluid in a special tool holder. The process not only improves surface finish but also imposes favorable compressive residual stresses in functional surfaces, which can lead to long fatigue life. Most research in the past focused on experimental studies. There is still a special need for a reliable finite element method (FEM) model that provides a fundamental understanding of the process mechanics. In this study, two-dimensional (2D) and three-dimensional FEM models for hard roller burnishing were established. The developed 2D FEM model was used to study the effects of process parameters (i.e., burnishing pressure, feed rate) on surface finish and residual stresses. The simulation results were evaluated and compared to the experimental data. Results show that the established FEM model could predict the residual stresses and provided useful information for the effect of process parameters. Both FEM and experiments show that burnishing pressure is the most influence, where high burnishing pressure produces less roughness and more compressive residual stress at the surface.

Automated Fracture Mechanics and Fatigue Analyses Based on Three-Dimensional Finite Elements

2015 ◽  
Vol 137 (6) ◽  
Author(s):  
Hitoshi Nakamura ◽  
Wenwei Gu ◽  
Seiichi Tajima ◽  
Osamu Hazama
Keyword(s):  
Finite Element ◽  
Crack Propagation ◽  
Three Dimensional ◽  
3D Fem ◽  
Element Mesh ◽  
Fem Model ◽  
Steel Pipes ◽  
Fatigue Initiation ◽  
Propagation Analysis ◽  
History Of

This paper describes the structure and application of a software system that automates the fatigue initiation and crack propagation analysis based on finite element method (FEM). The system automatically performs necessary procedures to track propagation history of cracks: insertion of a crack and updating of three-dimensional (3D) finite element mesh in accordance with the crack propagation. The system is equipped with a function to automatically perform fatigue analyses using the stress–strain histories at nodes of a 3D FEM model. Some analyses for several examples were carried out for validation. The important example is the surface crack propagation in steel pipes with residual stress.

scholarly journals Optimum Design of Steel Trapezoidal Box-Girders Using Finite Element Method

2018 ◽  
Vol 7 (4.20) ◽  
pp. 325 ◽  
Author(s):  
Abbas H. Mohammed ◽  
Khattab S. Abdul-Razzaq
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Optimum Design ◽  
Three Dimensional ◽  
Financial Structure ◽  
Box Girders ◽  
Component Programming ◽  
Volume Minimization ◽  
The Ideal ◽  
Element Method

The target of basic plan is to choose part sizes with the ideal proportioning of the in general auxiliary geometry. Regular steel trapezoidal box-supports have been utilized generally in different designing fields. The target of this examination is to create three-dimensional limited component display for the size improvement of steel trapezoidal box-braces. The limited component programming bundle ANSYS was utilized to decide the ideal cross segment measurement for the steel trapezoidal-box support. Two target capacities were considered in this investigation which are: minimization of the strain vitality and minimization of the volume. The plan factors are the width of the best spine, the width of the base rib, the thickness of the best rib, the thickness of the base rib, the stature of the support and the thickness of the networks. The imperatives considered in this examination are the ordinary and shear worry in steel brace and the dislodging at mid-length of the support. Improvement consequences of steel brace show that the ideal territory of cross segment for the strain vitality minimization is more noteworthy than the ideal for volume minimization by 6 %. The base cross area is the financial structure, hence the volume minimization is more pertinence for steel brace advancement.  

Evaluation of Intensity of Singularity at 3D Piezoelectric Bonded Joints Using a Conservative Integral

2015 ◽  
Author(s):  
Chonlada Luangarpa ◽  
Hideo Koguchi
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Electric Potential ◽  
Three Dimensional ◽  
Stress Singularity ◽  
Bonded Joints ◽  
Conservative Integral ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

In the present study, a conservative integral based on the Betti reciprocal principle is formulated in order to obtain the intensity of singularity at a vertex of the interface in three-dimensional piezoelectric bi-material bonded joints. To our knowledge, there are few studies on the determination of the intensity of singularity in the three-dimensional piezoelectric bonded joints. In addition, no study on the determination of the intensity of singularity in the 3D piezoelectric bonded joints using the conservative integral has been conducted. Eigenanalysis formulated using a three-dimensional finite element method (FEM) is used to calculate the order of stress singularity, angular variables of mechanical displacements, stresses, electric displacements and electric potential. In order to investigate the influence of an integral area on the accuracy of the results, models with various integral areas are used. The results are compared with those obtained from FEM.

DESIGN STRATEGY OF THREE-DIMENSIONAL PRINTED CAGES TO REDUCE IMPACT-INDUCED DEBRIS ALONG THE LOAD-TRANSFERRING PATH

2021 ◽  
pp. 2050021
Author(s):  
Shang-Chih Lin ◽  
Yu-Pao Hsu ◽  
Ching-Hsiao Yu ◽  
Chun-Ming Chen ◽  
Po-Quang Chen
Keyword(s):  
Finite Element ◽  
Cellular Structure ◽  
Three Dimensional ◽  
Peak Stress ◽  
Transforaminal Lumbar Interbody Fusion ◽  
Design Strategy ◽  
Cellular Structures ◽  
The Finite Element Method ◽  
3D Printed ◽  
The Impact

Peri-implant debris certainly lead to osteolysis, necrosis, pseudotumor formation, tissue granulation, fibrous capsule contractions, and even implant failure. For the three-dimensional (3D) printed cage, impaction during cage insertion is one of the most potential sources of fracture debris. A finite-element study was carried out to reduce the impact-induced debris of the 3D-printed cage. This study focused on the design strategy of solid and cellular structures along the load-transferring path. Using the finite-element method, the cellular structure of the transforaminal lumbar interbody fusion (TLIF) cage was systematically modified in the following four variations: a noncellular cage (NC), a fully cellular (FC) cage, a solid cage with a cellular structure in the middle concave (MC) zone, and a strengthened cage (SC) in the MC zone. Three comparison indices were considered: the stresses at the cage-instrument interfaces, in the MC zone, and along the specific load-transferring path. The NC and FC were the least and most highly stressed variations at the cage-instrument interfaces and in the MC zone, respectively. Along the entirely load-transferring path, the FC was still the most highly stressed variation. It showed a higher risk of stress fracture for the FC cage. For the MC and SC, the MC zone was consistently more stressed than the directly impacted zone. The further strengthened design of the SC had a lower peak stress (approximately 29.2%) in the MC zone compared with the MC. Prior to 3D printing, the load-transferring path from the cage-instrument interfaces to the cage-tissue interfaces should be determined. The cage-instrument interfaces should be printed as a solid structure to avoid impact-induced fracture. The other stress-concentrated zones should be cautiously designed to optimize the coexistence strategy of the solid and cellular structures.

Torque capacity of the multilayer interference fit based on a friction coefficient prediction model

2021 ◽  
pp. 135065012110397
Author(s):  
Ke Ning ◽  
Jianmei Wang ◽  
Dan Xiang ◽  
Dingbang Hou
Keyword(s):  
Finite Element ◽  
Theoretical Model ◽  
Friction Coefficient ◽  
Prediction Model ◽  
Three Dimensional ◽  
Element Model ◽  
Maximum Relative Error ◽  
Interference Fit ◽  
Mathematical Expressions ◽  
Torque Capacity

This paper proposes the theoretical model of a multilayer interference fit and gives out the relational expression between radial interference and friction coefficient. Taking the typical wind turbine's shrink disk of a three-layer interference fit structure as an example, special experimental equipment is developed to test the torque capacity. Based on experimental results and the theoretical model, the mathematical expressions of radial interference and assembly stroke for friction coefficient are obtained by polynomial fitting, and the prediction model of friction coefficient is established. The three-dimensional finite element model of a shrink disk is constructed by applying the friction coefficient prediction model. With the mathematical expressions of radial interference and assembly stroke for the torque capacity, the rules of main dimension parameters and torque capacity are analyzed. The maximum relative error between experiment and simulation is 8.2%, which shows the feasibility of finite element simulation. The results of our study have certain guidance for the prediction of friction coefficient and the manufacture of the multilayer interference fit.

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