scholarly journals Revealing the nanoindentation response of a single cell using a 3D structural finite element model

2021 ◽  
Author(s):  
Wenjian Yang ◽  
Damien Lacroix ◽  
Lay Poh Tan ◽  
Jinju Chen
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Cell Mechanics ◽  
Cone Angle ◽  
Element Model ◽  
Homogeneous Material ◽  
Physiological Conditions ◽  
Dependent Cell ◽  
Core Shell Structure ◽  
Indenter Geometry

AbstractChanges in the apparent moduli of cells have been reported to correlate with cell abnormalities and disease. Indentation is commonly used to measure these moduli; however, there is evidence to suggest that the indentation protocol employed affects the measured moduli, which can affect our understanding of how physiological conditions regulate cell mechanics. Most studies treat the cell as a homogeneous material or a simple core–shell structure consisting of cytoplasm and a nucleus: both are far from the real structure of cells. To study indentation protocol-dependent cell mechanics, a finite element model of key intracellular components (cortex layer, cytoplasm, actin stress fibres, microtubules, and nucleus) has instead been developed. Results have shown that the apparent moduli obtained with conical indenters decreased with increasing cone angle; however, this change was less significant for spherical indenters of increasing radii. Furthermore, the interplay between indenter geometry and intracellular components has also been studied, which is useful for understanding structure-mechanics-function relationships of cells.

scholarly journals Development technique for deep drawing without blank holder to produce circular cup of brass alloy

2015 ◽  
Vol 4 (1) ◽  
pp. 187 ◽  
Author(s):  
Ali Hassan Saleh ◽  
Ammer Khalaf Ali
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Deep Drawing ◽  
Cone Angle ◽  
Element Model ◽  
Drawing Ratio ◽  
Clearance Ratio ◽  
Blank Holder ◽  
Half Cone ◽  
Half Cone Angle

Of this technique compared to the conventional deep drawing is that the circular cup can be carried out in single action press with limit In this paper a new mechanism for deep drawing was proposed to produce circular cup from thin plate without blank holder. In this technique the die assembly includes punch, die and die-punch. A 2D axisymmetric finite element model was built using DEFORM software. Effect of die geometry (half- cone angle) on maximum load, thickness distribution, strain distribution and effect of clearance ratio between punch and (die-punch) on the wrinkling of the cup were investigated. Three half-cone angles of die (15o, 30o and 45o) were used for forming sheet metal of brass (CuZn37) which had initial thickness of (1mm) at four clearance ratio (c/t) for die of 30o half-cone angle. Finite element model results showed good agreement with experimental results. Die of 30o half-cone angle with clearance ratio (c/t) of 0.9 gave the best product without wrinkling. The main advantage drawing ratio (LDR) of 1.86 and blank diameter to blank thickness ratio (d/t) < 86.

Structural Optimization of Packer’ Cone with Material Properties and Mechanics Parameters Based on ANSYS

2012 ◽  
Vol 252 ◽  
pp. 172-175
Author(s):  
Zhi Ping Guo ◽  
Wei Guo ◽  
Yan Fei Wang ◽  
Guan Fu Li ◽  
Yan Zheng Lu
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Material Properties ◽  
Theoretical Basis ◽  
Cone Angle ◽  
Element Model ◽  
Mechanical Analysis ◽  
Calculation Results ◽  
Set Up ◽  
The Finite Element Model

Cone is one part of a packer. To understand the seal effectiveness of the packer, mechanical analysis must be made for it. The finite element model of packer is set up and packer minimum setting load changes are calculated under different climb angle of cone. Results show that reduce the cone angle of climb can make the packer sealing load significantly lower.The calculation results provide the theoretical basis for the real operation.

Imperfection Analysis of a Bistable Shell

2011 ◽  
Author(s):  
K. R. Ford ◽  
M. R. Brake ◽  
D. J. VanGoethem ◽  
A. Cobert
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Static Stability ◽  
Energy Curve ◽  
Homogeneous Material ◽  
Element Mesh ◽  
Buckling Loads ◽  
Mechanical Memory ◽  
Nonlinear Finite Element Model

Bistable compliant flexures serve as mechanical memory and threshold devices for switches and sensors. One class of bistable compliant flexures is the annular, spherical shell, termed a bistable snap disc. These structures offer flexibility for mechanical memory and threshold devices because large changes in buckling loads can be achieved without significantly modifying the geometry. The sensitivity of these bistable snap discs to imperfections, however, prevents them from withstanding pre-buckling loads predicted by idealized models. A method to incorporate geometric imperfections into an existing finite element mesh of the idealized geometry using a set of orthonormal polynomials, specifically the annular Zernike polynomials, is proposed in this paper. A sensitivity analysis of five terms from the Zernike polynomial expansion is performed with a geometrically nonlinear finite element model to identify their effect on buckling, snap-through, and quasi-static stability. The effects of the perturbations are established by identifying key points on a force-deflection curve and potential energy curve. Results show that the geometric perturbations may account for the discrepancy in buckling between the idealized model and experiments. Error between the experiments and the model with geometric perturbations persist because the actual imperfections of the discs used in the experiments have not yet been characterized, and the finite element model does not account for non-homogeneous material properties and residual stresses.

Finite Element Simulation of Tire-Rim Interface

1989 ◽  
Vol 17 (4) ◽  
pp. 305-325 ◽  
Author(s):  
N. T. Tseng ◽  
R. G. Pelle ◽  
J. P. Chang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Finite Element Simulation ◽  
Contact Pressure ◽  
Element Model ◽  
Experimental Measurements ◽  
Inflation Pressure ◽  
Interference Fit ◽  
Element Simulation ◽  
Rubber Composite

Abstract A finite element model was developed to simulate the tire-rim interface. Elastomers were modeled by nonlinear incompressible elements, whereas plies were simulated by cord-rubber composite elements. Gap elements were used to simulate the opening between tire and rim at zero inflation pressure. This opening closed when the inflation pressure was increased gradually. The predicted distribution of contact pressure at the tire-rim interface agreed very well with the available experimental measurements. Several variations of the tire-rim interference fit were analyzed.

Torsional Analysis of a Steel Cord-Rubber Tire Belt Structure

1996 ◽  
Vol 24 (4) ◽  
pp. 339-348 ◽  
Author(s):  
R. M. V. Pidaparti
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Composite Structures ◽  
Three Dimensional ◽  
Element Model ◽  
Torsional Stiffness ◽  
Element Analysis ◽  
Rubber Belt ◽  
Steel Cord ◽  
Torsional Analysis

Abstract A three-dimensional (3D) beam finite element model was developed to investigate the torsional stiffness of a twisted steel-reinforced cord-rubber belt structure. The present 3D beam element takes into account the coupled extension, bending, and twisting deformations characteristic of the complex behavior of cord-rubber composite structures. The extension-twisting coupling due to the twisted nature of the cords was also considered in the finite element model. The results of torsional stiffness obtained from the finite element analysis for twisted cords and the two-ply steel cord-rubber belt structure are compared to the experimental data and other alternate solutions available in the literature. The effects of cord orientation, anisotropy, and rubber core surrounding the twisted cords on the torsional stiffness properties are presented and discussed.

Sign in / Sign up

Export Citation Format

Share Document