Inverse Finite Element Analysis of the Indentation Response of Human Cervical Tissue

2013 ◽  
Author(s):  
Kristin Myers ◽  
Wang Yao ◽  
Kyoko Yoshida ◽  
Joy Vink ◽  
Noelia Zork ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Viscoelastic Material ◽  
Material Model ◽  
Spherical Indentation ◽  
Cervical Tissue ◽  
Tissue Slices ◽  
Element Analysis ◽  
Material Parameters ◽  
Inverse Finite Element Analysis

The mechanical function of the cervix is crucial during pregnancy when it is required to resist the compressive and tensile forces generated from the growing fetus. Pathologies of the cervical extracellular matrix (ECM), premature cervical remodeling, and alterations of cervical material properties have been implicated in placing women at high-risk for preterm birth (PTB). To understand the mechanical role of the cervix during pregnancy and to potentially identify etiologies for PTB, the overall goal of our group is to quantify ECM-material property relationships in normal and diseased human cervical tissue. In this study we present an inverse finite element analysis (IFEA) that optimizes material parameters of a viscoelastic material model to fit the stress-relaxation response of excised tissue slices to spherical indentation. Here we detail our IFEA methodology, report viscoelastic material parameters for cervical tissue slices from nonpregnant (NP) and pregnant (PG) hysterectomy patients, and report slice-by-slice data for whole cervical tissue specimens.

Lifetime Prediction of Tires with Regard to Oxidative Aging5

2008 ◽  
Vol 36 (1) ◽  
pp. 63-79 ◽  
Author(s):  
L. Nasdala ◽  
Y. Wei ◽  
H. Rothert ◽  
M. Kaliske
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Temperature Distribution ◽  
Superposition Principle ◽  
Accelerated Aging ◽  
Material Model ◽  
Aging Behavior ◽  
Element Analysis ◽  
Material Parameters ◽  
Reaction Processes

Abstract It is a challenging task in the design of automobile tires to predict lifetime and performance on the basis of numerical simulations. Several factors have to be taken into account to correctly estimate the aging behavior. This paper focuses on oxygen reaction processes which, apart from mechanical and thermal aspects, effect the tire durability. The material parameters needed to describe the temperature-dependent oxygen diffusion and reaction processes are derived by means of the time–temperature–superposition principle from modulus profiling tests. These experiments are designed to examine the diffusion-limited oxidation (DLO) effect which occurs when accelerated aging tests are performed. For the cord-reinforced rubber composites, homogenization techniques are adopted to obtain effective material parameters (diffusivities and reaction constants). The selection and arrangement of rubber components influence the temperature distribution and the oxygen penetration depth which impact tire durability. The goal of this paper is to establish a finite element analysis based criterion to predict lifetime with respect to oxidative aging. The finite element analysis is carried out in three stages. First the heat generation rate distribution is calculated using a viscoelastic material model. Then the temperature distribution can be determined. In the third step we evaluate the oxygen distribution or rather the oxygen consumption rate, which is a measure for the tire lifetime. Thus, the aging behavior of different kinds of tires can be compared. Numerical examples show how diffusivities, reaction coefficients, and temperature influence the durability of different tire parts. It is found that due to the DLO effect, some interior parts may age slower even if the temperature is increased.

Elastic and elastic-plastic finite element analysis of hollow tubes with axisymmetric internal projections under combined axial and pressure loading

2001 ◽  
Vol 36 (4) ◽  
pp. 373-390 ◽  
Author(s):  
S. J Hardy ◽  
M. K Pipelzadeh ◽  
A. R Gowhari-Anaraki
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Internal Pressure ◽  
Plastic Material ◽  
Axial Loading ◽  
Material Model ◽  
Pressure Loading ◽  
Element Analysis ◽  
Elastic Plastic ◽  
Applied Loading

This paper discusses the behaviour of hollow tubes with axisymmetric internal projections subjected to combined axial and internal pressure loading. Predictions from an extensive elastic and elastic-plastic finite element analysis are presented for a typical geometry and a range of loading combinations, using a simplified bilinear elastic-perfectly plastic material model. The axial loading case, previously analysed, is extended to cover the additional effect of internal pressure. All the predicted stress and strain data are found to depend on the applied loading conditions. The results are normalized with respect to material properties and can therefore be applied to geometrically similar components made from other materials, which can be represented by the same material models.

scholarly journals Simulasi Pembebanan Komponen Bender pada Desain Mesin Begel Fabricator Menggunakan Software Autodesk Inventor 2020

2021 ◽  
Vol 2 (2) ◽  
pp. 93-97
Author(s):  
Satriawan Dini Hariyanto ◽  
Wikan Kurniawan
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Cast Iron ◽  
Mild Steel ◽  
Modulus Of Elasticity ◽  
Material Parameter ◽  
Element Analysis ◽  
Material Parameters ◽  
Constituent Material ◽  
Loading Parameter

Stress analysis of the bender components in the design of the begel fabricator machine was carried out using FEA (Finite Element Analysis) with three variations of the constituent material parameters, namely 6061 aluminum, mild steel, and cast iron with a modulus of elasticity of 68.9 GPa, 220 GPa, 120.5 GPa, respectively. The test is carried out by a loading parameter 2520 MPa and fixed constraint. The maximum von misses stress and displacement obtained for each material parameter components using aluminum, mild steel, and cast iron are 17.78 MPa; 0.00765, 17.49 MPa; 0.00229, 17.62 MPa; 0.00427 respectively.

Finite element analysis of spherical indentation to study pile-up/sink-in phenomena in steels and experimental validation

2012 ◽  
Vol 54 (1) ◽  
pp. 74-83 ◽  
Author(s):  
V. Karthik ◽  
P. Visweswaran ◽  
Anand Bhushan ◽  
D.N. Pawaskar ◽  
K.V. Kasiviswanathan ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Experimental Validation ◽  
Spherical Indentation ◽  
Element Analysis ◽  
Pile Up

Prediction of Cutting Force in Bone Cutting Using Finite Element Analysis

2021 ◽  
Author(s):  
Varatharajan Prasannavenkadesan ◽  
Ponnusamy Pandithevan
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Cutting Force ◽  
Material Model ◽  
Tensile Tests ◽  
Bovine Bone ◽  
Element Analysis ◽  
Cutting Processes ◽  
Parameter Values ◽  
First Time

Abstract In orthopedic surgery, bone cutting is an indispensable procedure followed by the surgeons to treat the fractured and fragmented bones. Because of the unsuitable parameter values used in the cutting processes, micro crack, fragmentation, and thermal osteonecrosis of bone are observed. Therefore, prediction of suitable cutting force is essential to subtract the bone without any adverse effect. In this study, the Cowper-Symonds model for bovine bone was developed for the first time. Then the developed model was coupled with the finite element analysis to predict the cutting force. To determine the model constants, tensile tests with different strain rates (10−5/s, 10−4/s, 10−3/s, and 1/s) were conducted on the cortical bone specimens. The developed material model was implemented in the bone cutting simulation and validated with the experiments.

Finite Element Analysis of Ceramic Coating Systems Under Spherical Indentation With Metallic Interlayer: Part I — Uncracked Coatings

2005 ◽  
Author(s):  
Minh-Quy Le ◽  
Jin-Woo Yi ◽  
Seock-Sam Kim
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Coating Thickness ◽  
Radial Stress ◽  
Ceramic Coating ◽  
Ceramic Coatings ◽  
Spherical Indentation ◽  
Model Parameters ◽  
Element Analysis ◽  
Plastic Damage

Spherical indentation problems of ceramic coatings/metallic inter-layer/ductile substrate were investigated numerically by axisymmetric finite element analysis (FEA) for two typical ceramic coatings with relatively high and low elastic modulus deposited on aluminum alloy and carbon steel. Various indenter radius-coating thickness ratios and interlayer thickness-coating thickness ratios were used in the modeling. Radial stress distribution and plastic damage zones evolution were discussed in connection with model parameters. The results showed that the suitable metallic interlayer could improve resistance of ceramic coating systems through reducing the peak tensile radial stress on the surface and interface of ceramic coatings and plastic damage zone size in the substrate under spherical indentation.

Sign in / Sign up

Export Citation Format

Share Document