Stress-strain analysis of high-velocity machine rotors using three-dimensional photoelastic models

1996 ◽  
Author(s):  
A. D. Kondratyev ◽  
B. N. Ushakov
Keyword(s):  
High Velocity ◽  
Three Dimensional ◽  
Strain Analysis ◽  
Stress Strain

scholarly journals Strain Analysis on Electrochemical Failures of Nanoscale Silicon Electrode Based on Three-Dimensional In Situ Measurement

2020 ◽  
Vol 10 (2) ◽  
pp. 468 ◽  
Author(s):  
Zhifeng Qi ◽  
Zhongqiang Shan ◽  
Weihao Ma ◽  
Linan Li ◽  
Shibin Wang ◽  
...  
Keyword(s):  
Silicon Film ◽  
Three Dimensional ◽  
Strain Analysis ◽  
Image Correlation ◽  
Mechanical Parameters ◽  
Stress Strain ◽  
Full Field ◽  
Battery Capacity

Nanoscale silicon film electrodes in Li-ion battery undergo great deformations leading to electrochemical and mechanical failures during repeated charging-discharging cycles. In-situ experimental characterization of the stress/strain in those electrodes still faces big challenges due to remarkable complexity of stress/strain evolution while it is still hard to predict the association between the electrode cycle life and the measurable mechanical parameters. To quantificationally investigate the evolution of the mechanical parameters, we develop a new full field 3D measurement method combining digital image correlation with laser confocal profilometry and propose a strain criterion of the failure based on semi-quantitative analysis via mean strain gradient (MSG). The experimental protocol and results illustrate that the revolution of MSG correlates positively with battery capacity decay, which may inspire future studies in the field of film electrodes.

scholarly journals Direct method of load simulation in hull strength analysis of catamaran

2020 ◽  
Vol S-I (2) ◽  
pp. 230-236
Author(s):  
R. Chistyakov ◽  
◽  
P. Mudrik ◽  
Keyword(s):  
Direct Method ◽  
Three Dimensional ◽  
Strain Analysis ◽  
Strength Analysis ◽  
Ship Motions ◽  
Regular Waves ◽  
Stress Strain ◽  
Internal Forces ◽  
External Forces ◽  
Force Calculation

This paper discusses three-dimensional formulation for the problem of external forces acting on catamaran hull, as well as performs stress-strain state analysis of the structures affected by the loads thus calculated. The purpose of this study was to develop a modern methodology for joint solution to the first and the second problem of naval structural mechanics based on panelpotential and finite-element models in three-dimensional formulation for the conditions of still water and regular waves. The study discusses various formulations of the problem and various methods of external force calculation. External load is estimated in two formulations: static (based on hydrostatic methods) and stationary dynamic (based on the linear theory of ship motions). Also, external forces and their respective stresses were estimated as per the procedure of the classification society. The case study of a catamaran illustrates the process of load calculation and stress-strain analysis, giving the results for various external forces, with their assessment and analysis of internal forces and displacements induced by them. The study yielded rather handy technique for stress-strain analysis of catamaran hull in 3D formulation, including spatial static trimming in still water and in waves of given profile, as well as calculation of displacement amplitudes in regular waves, calculation of phase pressure fields and accelerations on catamaran hull, with further export of calculated external loads to FE analysis software for stressstrain investigation of structurally similar model needed to understand how conservative this model is.

Delamination in the scoring and folding of paperboard

TAPPI Journal ◽  
2012 ◽  
Vol 11 (1) ◽  
pp. 61-66 ◽  
Author(s):  
DOEUNG D. CHOI ◽  
SERGIY A. LAVRYKOV ◽  
BANDARU V. RAMARAO
Keyword(s):  
Finite Element ◽  
Plane Deformation ◽  
Strain Analysis ◽  
Local Strain ◽  
Uniaxial Stress ◽  
Material Model ◽  
Element Model ◽  
Plastic Behavior ◽  
Stress Strain ◽  
Strain Fields

Delamination between layers occurs during the creasing and subsequent folding of paperboard. Delamination is necessary to provide some stiffness properties, but excessive or uncontrolled delamination can weaken the fold, and therefore needs to be controlled. An understanding of the mechanics of delamination is predicated upon the availability of reliable and properly calibrated simulation tools to predict experimental observations. This paper describes a finite element simulation of paper mechanics applied to the scoring and folding of multi-ply carton board. Our goal was to provide an understanding of the mechanics of these operations and the proper models of elastic and plastic behavior of the material that enable us to simulate the deformation and delamination behavior. Our material model accounted for plasticity and sheet anisotropy in the in-plane and z-direction (ZD) dimensions. We used different ZD stress-strain curves during loading and unloading. Material parameters for in-plane deformation were obtained by fitting uniaxial stress-strain data to Ramberg-Osgood plasticity models and the ZD deformation was modeled using a modified power law. Two-dimensional strain fields resulting from loading board typical of a scoring operation were calculated. The strain field was symmetric in the initial stages, but increasing deformation led to asymmetry and heterogeneity. These regions were precursors to delamination and failure. Delamination of the layers occurred in regions of significant shear strain and resulted primarily from the development of large plastic strains. The model predictions were confirmed by experimental observation of the local strain fields using visual microscopy and linear image strain analysis. The finite element model predicted sheet delamination matching the patterns and effects that were observed in experiments.

Stress-Strain Analysis and Simulation for Estimation of Cutting Forces on the Skin

2015 ◽  
Vol 9 (6) ◽  
pp. 583
Author(s):  
Dario German Buitrago ◽  
Luis Carlos Ruíz ◽  
Olga Lucia Ramos
Keyword(s):  
Cutting Forces ◽  
Strain Analysis ◽  
Stress Strain

Validation of three‐dimensional echocardiographic principal strain analysis for assessing left ventricular contractility: An animal study

2019 ◽  
Vol 46 (5) ◽  
pp. 2137-2144
Author(s):  
Sahmin Lee ◽  
Seunghyun Choi ◽  
Sehwan Kim ◽  
Yeongjin Jeong ◽  
Kyusup Lee ◽  
...  
Keyword(s):  
Animal Study ◽  
Three Dimensional ◽  
Strain Analysis ◽  
Left Ventricular ◽  
Principal Strain ◽  
Ventricular Contractility ◽  
Left Ventricular Contractility

Stress-strain curve of paper revisited

2012 ◽  
Vol 27 (2) ◽  
pp. 318-328 ◽  
Author(s):  
Svetlana Borodulina ◽  
Artem Kulachenko ◽  
Mikael Nygårds ◽  
Sylvain Galland
Keyword(s):  
Three Dimensional ◽  
Strain Curve ◽  
Failure Behavior ◽  
Three Dimensional Model ◽  
Stress Strain Curve ◽  
Stress Strain ◽  
Fiber Network ◽  
Bonding Parameters ◽  
Particle Level ◽  
The Impact

Abstract We have investigated a relation between micromechanical processes and the stress-strain curve of a dry fiber network during tensile loading. By using a detailed particle-level simulation tool we investigate, among other things, the impact of “non-traditional” bonding parameters, such as compliance of bonding regions, work of separation and the actual number of effective bonds. This is probably the first three-dimensional model which is capable of simulating the fracture process of paper accounting for nonlinearities at the fiber level and bond failures. The failure behavior of the network considered in the study could be changed significantly by relatively small changes in bond strength, as compared to the scatter in bonding data found in the literature. We have identified that compliance of the bonding regions has a significant impact on network strength. By comparing networks with weak and strong bonds, we concluded that large local strains are the precursors of bond failures and not the other way around.

Sign in / Sign up

Export Citation Format

Share Document