Plasticity Model and Numerical Simulation of Extruded Oilseeds in Closed Cell

2011 ◽  
Vol 304 ◽  
pp. 235-240
Author(s):  
Xiao Zheng ◽  
Ya Xin Zhang ◽  
Guo Xiang Lin ◽  
Zhi Xian Sun
Keyword(s):  
Numerical Simulation ◽  
Constitutive Equations ◽  
Theoretical Basis ◽  
Inverse Method ◽  
Yield Criterion ◽  
Model Parameters ◽  
Plasticity Model ◽  
Power Curve ◽  
Experimental Stress ◽  
Closed Cell

By using of Kuhn`s yield criterion, plasticity constitutive equations of extruded oilseeds in a closed cylinderical cell were developed. The model parameters were identified from experimental stress—strain using an inverse method. The maximum relative deviations between the measured and the simulated value of soybean and cottonseed are 8.5% and 5.1% respectively, and the average relative deviations are 4.9% and 3.8% respectively. The results of numerical simulation for confined pressing of granular soybeans and cottonseeds in the closed cylinderical cell indicated the following facts that granular soybeans and cottonseeds conform to the model of three power curve, the plasticity constitutive equations can describe the plastic deformation for extruded soybean and cottonseed, and Kuhn`s yield criterion can be used as theoretical basis for plasticity model of granular soybeans and cottonseeds.

Plasticity Model of Extruded Peanuts under Mechanical Pressing

2011 ◽  
Vol 55-57 ◽  
pp. 20-25
Author(s):  
Xiao Zheng ◽  
Ya Xin Zhang ◽  
Guo Xiang Lin ◽  
Zhi Xian Sun
Keyword(s):  
Constitutive Equations ◽  
Inverse Method ◽  
Yield Criterion ◽  
Strain Curve ◽  
Model Parameters ◽  
Plasticity Model ◽  
Stress Strain ◽  
Relative Deviation ◽  
Maximum Relative Deviation ◽  
Mechanical Pressing

The experiments for stress—strain and confined pressing of granular peanuts by uniaxial pressing were carried out. The results show that granular peanuts conform to the model of three power curve. By using of Kuhn`s yield criterion, plasticity constitutive equations of granular peanuts were developed. The model parameters were determined from experimental stress—strain curve using an inverse method. The maximum relative deviation between the measured and the simulated value of strain is 5.4%, and the average relative deviation is 3.5%. Results indicated that the plasticity constitutive equations can describe the plastic deformation for extruded peanut, and Kuhn`s yield criterion can be used as theoretical basis for plasticity model of granular peanuts.<b></b>

Modelling and numerical simulation of thick sheet double slitting process using continuum damage mechanics

2014 ◽  
Vol 23 (8) ◽  
pp. 1150-1167 ◽  
Author(s):  
Yosr Ghozzi ◽  
Carl Labergere ◽  
Khemais Saanouni ◽  
Anthony Parrico
Keyword(s):  
Numerical Simulation ◽  
Constitutive Equations ◽  
Damage Mechanics ◽  
Continuum Damage Mechanics ◽  
Thick Sheet ◽  
Technological Parameters ◽  
Strongly Coupled ◽  
Mixed Hardening ◽  
Elasto Plasticity ◽  
Fully Coupled

This work concerns the modelling and numerical simulation of specific thick sheet cutting process using advanced constitutive equations accounting for elasto-plasticity with mixed hardening fully coupled with isotropic ductile damage. First, the complex kinematics of the different tools is modelled with specific boundary conditions. Second, the fully and strongly coupled constitutive equations are summarized and the associated numerical aspects are shortly presented. An inverse material identification procedure is used to determine the convenient values of the material parameters. Finally, the double slitting process is numerically simulated and the influence of the main technological parameters studied focusing on the cutting forces.

Research on Propagation Numerical Simulation of Blast Shock Waves in Subway Station

2013 ◽  
Vol 380-384 ◽  
pp. 1725-1728
Author(s):  
Yang Hu ◽  
Huai Yu Kang
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Experimental Study ◽  
Shock Waves ◽  
Theoretical Basis ◽  
Damage Effect ◽  
Subway Station ◽  
Element Calculation ◽  
Dynamic Finite Element ◽  
Walking Pattern

In this paper, we Research on Propagation Numerical Simulation and damage effect of Blast Shock Waves in Subway Station by using LS-DYNA dynamic finite element calculation program , the results reproduce the formation process of the explosive flow field, and analysis the shock wave waveform, attenuation and walking pattern, provides the theoretical basis for further experimental study.

Simulation and Analysis of Swing Motion of Lifting Load System on Rescue Vehicle

2012 ◽  
Vol 538-541 ◽  
pp. 725-729
Author(s):  
Han Ming Liu ◽  
Heng Zhao ◽  
Ning Li
Keyword(s):  
Numerical Simulation ◽  
Theoretical Basis ◽  
Safety Assessment ◽  
Kinematic Model ◽  
Excitation Frequency ◽  
Lagrange’S Equation ◽  
Set Up

In lifting, remoted operated dive vehicle（ROV） may swing with the effect of wave. Based on the general form of Lagrange’s equation, a 3-DOF nonlinear swing motion kinematic model was set up. The kinematic response was studied using methods of numerical simulation. The results demonstrated that the kinematic response depends on the length of cable, lifting speed and excitation frequency. Conclusions drawn from this work can be used for safety assessment and theoretical basis for lifting ROV.

scholarly journals Complex Dynamical Behavior of a Predator-Prey System with Group Defense

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Jianglin Zhao ◽  
Min Zhao ◽  
Hengguo Yu
Keyword(s):  
Numerical Simulation ◽  
Theoretical Basis ◽  
Dynamical Behavior ◽  
Turing Instability ◽  
Equilibrium Density ◽  
Prey Refuge ◽  
Predator Prey ◽  
Prey System ◽  
Group Defense ◽  
Complex Dynamical Behavior

A diffusive predator-prey system with prey refuge is studied analytically and numerically. The Turing bifurcation is analyzed in detail, which in turn provides a theoretical basis for the numerical simulation. The influence of prey refuge and group defense on the equilibrium density and patterns of species under the condition of Turing instability is explored by numerical simulations, and this shows that the prey refuge and group defense have an important effect on the equilibrium density and patterns of species. Moreover, it can be obtained that the distributions of species are more sensitive to group defense than prey refuge. These results are expected to be of significance in exploration for the spatiotemporal dynamics of ecosystems.

FEM Analysis of Contact for Converter Spherical Hinge

2013 ◽  
Vol 365-366 ◽  
pp. 331-334
Author(s):  
Xue Ping Ren ◽  
Jian Da Gao
Keyword(s):  
Numerical Simulation ◽  
Thermal Stress ◽  
Optimum Design ◽  
Theoretical Basis ◽  
Fem Analysis ◽  
Structure Design ◽  
Coupling Field ◽  
Main Components ◽  
Spherical Hinge

The role of converter spherical hinge is one of the main components, combined with practical work and With help of FEM, Thermal Stress coupling field of spherical washer can been obtained through numerical simulation. The result supplies substantial theoretical basis for further structure design and optimum design of mechanism.

scholarly journals Discussion on the Theoretical Basis for Cross-Over Method Applied to Downhole Wave Velocity Test

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Qing Dong ◽  
Zheng-hua Zhou ◽  
Su Jie ◽  
Bing Hao ◽  
Yuan-dong Li
Keyword(s):  
Numerical Simulation ◽  
Numerical Simulations ◽  
Wave Velocity ◽  
Theoretical Basis ◽  
Influence Factors ◽  
P Wave ◽  
Engineering Practice ◽  
S Wave ◽  
Simulation Results ◽  
The Cross

At engineering practice, the theoretical basis for the cross-over method, used to obtain shear wave arrival time in the downhole method of the wave velocity test by surface forward and backward strike, is that the polarity of P-wave keeps the same, while the polarity of S-wave transforms when the direction of strike inverted. However, the characteristics of signals recorded in tests are often found to conflict with this theoretical basis for the cross-over method, namely, the polarity of the P-wave also transforms under the action of surface forward and backward strike. Therefore, 3D finite element numerical simulations were conducted to study the validity of the theoretical basis for the cross-over method. The results show that both shear and compression waves are observed to be in 180° phase difference between horizontal signal traces, consistent with the direction of excitation generated by reversed impulse. Furthermore, numerical simulation results prove to be reliable by the analytic solution; it shows that the theoretical basis for the cross-over method applied to the downhole wave velocity test is improper. In meanwhile, numerical simulations reveal the factors (inclining excitation, geophone deflection, inclination, and background noise) that may cause the polarity of the P-wave not to reverse under surface forward and backward strike. Then, as to reduce the influence factors, we propose a method for the downhole wave velocity test under surface strike, the time difference of arrival is based between source peak and response peak, and numerical simulation results show that the S-wave velocity by this method is close to the theoretical S-wave velocity of soil.

scholarly journals Coupling numerical model of hydraulic fracturing seepage in soft coal based on elastoplastic damage

2020 ◽  
Vol 198 ◽  
pp. 01038
Author(s):  
LI Liangwei
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Hydraulic Fracturing ◽  
Yield Criterion ◽  
Calculation Model ◽  
Field Application ◽  
Soft Coal ◽  
Plastic Shear Strain ◽  
Strain Relationship ◽  
Relationship Equation

In order to guide the field application of hydraulic fracturing of soft coal in coal mine, based on the elastic-plastic damage theory, the coupling numerical model of soft coal hydraulic fracturing seepage was studied. The porosity strain relationship equation, permeability strain relationship equation, the relationship between permeability and volume plastic tensile strain and volume plastic shear strain of coal and rock mass are derived, and the plastic correction equation and softening parameters are defined. The stress coupling equation and yield criterion are programmed and embedded into the finite difference software FLAC3D for numerical solution. The numerical simulation shows that the numerical calculation model of soft coal hydraulic fracturing conforms to the actual law, and the field fracturing radius investigation experiment is consistent with the numerical simulation results.

scholarly journals Analysis of Mathematics and Sustainability in an Impulsive Eutrophication Controlling System

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Hengguo Yu ◽  
Min Zhao ◽  
Qi Wang
Keyword(s):  
Numerical Simulation ◽  
Theoretical Basis ◽  
Algal Bloom ◽  
Critical Parameters ◽  
Critical Factors ◽  
Experiment Data ◽  
Threshold Functions ◽  
Controlling System ◽  
Best Value ◽  
Mathematical System

Eutrophication removal problems have captured the attention of biologists, mathematicians, and environmental scientists. Within this framework, an impulsive eutrophication controlling system is studied analytically and numerically. A key advantage of the eutrophication system is that it can be quite accurate to describe the interaction effect of some critical factors (fishermen catch and releasing small fry, etc.), which enables a systematic and logical procedure for fitting eutrophication mathematical system to real monitoring data and experiment data. Mathematical theoretical works have been pursuing the investigation of two threshold functions of some critical parameters under the condition of all species persistence, which can in turn provide a theoretical basis for the numerical simulation. Using numerical simulation works, we mainly focus on how to choose the best value of some critical parameters to ensure the sustainability of the eutrophication system so that the eutrophication removal process can be well developed with maximizing economic benefit. These results may be further extended to provide a basis for simulating the algal bloom in the laboratory and understanding the application of some impulsive controlling models about eutrophication removal problems.

Sign in / Sign up

Export Citation Format

Share Document