scholarly journals Loading equine oocytes with cryoprotective agents captured with a finite element method model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sercan Içli ◽  
Meisam Soleimani ◽  
Harriëtte Oldenhof ◽  
Harald Sieme ◽  
Peter Wriggers ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Spatial Information ◽  
Transport Model ◽  
Membrane Surface ◽  
Cellular Membrane ◽  
Freezing Injury ◽  
Fem Simulations ◽  
Cryoprotective Agents ◽  
Element Method

AbstractCryopreservation can be used to store equine oocytes for extended periods so that they can be used in artificial reproduction technologies at a desired time point. It requires use of cryoprotective agents (CPAs) to protect the oocytes against freezing injury. The intracellular introduction of CPAs, however, may cause irreversible osmotic damage. The response of cells exposed to CPA solutions is governed by the permeability of the cellular membrane towards water and the CPAs. In this study, a mathematical mass transport model describing the permeation of water and CPAs across an oocyte membrane was used to simulate oocyte volume responses and concomitant intracellular CPA concentrations during the exposure of oocytes to CPA solutions. The results of the analytical simulations were subsequently used to develop a phenomenological finite element method (FEM) continuum model to capture the response of oocytes exposed to CPA solutions with spatial information. FEM simulations were used to depict spatial differences in CPA concentration during CPA permeation, namely at locations near the membrane surface and towards the middle of the cell, and to capture corresponding changes in deformation and hydrostatic pressure. FEM simulations of the multiple processes occurring during CPA loading of oocytes are a valuable tool to increase our understanding of the mechanisms underlying cryopreservation outcome.

THE MECHANICAL PROPERTIES OF POROUS ALUMINUM USING FINITE ELEMENT METHOD SIMULATIONS AND COMPRESSION EXPERIMENTS

2013 ◽  
Vol 1580 ◽  
Author(s):  
Max Larner ◽  
Lilian P. Dávila
Keyword(s):  
Mechanical Properties ◽  
Finite Element Method ◽  
Finite Element ◽  
Relative Density ◽  
Alternative Energy ◽  
Sound Insulation ◽  
Full Potential ◽  
Fem Simulations ◽  
Al Foams ◽  
Element Method

ABSTRACTLightweight porous metallic materials are generally created through specialized processing techniques. Their unique structure gives these materials interesting properties which allow them to be used in diverse structural and insulation applications. In particular, highly porous Al structures (Al foams) have been used in aircraft components and sound insulation; however due to the difficulty in processing and random nature of the foams, they are not well understood and thus they have not yet been utilized to their full potential. The objective of this project was to determine whether a relationship exists between the relative density (porous density/bulk density) and the mechanical properties of porous Al structures. For this purpose, a combination of computer simulations and experiments was pursued to better understand possible relationships. A Finite Element Method (FEM)-based software, COMSOL Multiphysics 4.3, was used to model the structure and to simulate the mechanical behavior of porous Al structures under compressive loads ranging from 1-100 MPa. From these simulated structures, the maximum von Mises stress, volumetric strain, and other properties were calculated. These simulation results were compared against data from compression experiments performed using the Instron Universal Testing Machine (IUTM) on porous Al specimens created via a computernumerically-controlled (CNC) mill. CES EduPack software, a materials design program, was also used to estimate the mechanical properties of porous Al and open cell foams for values not available experimentally, and for comparison purposes. This program allowed for accurate prediction of the mechanical properties for a given percent density foam, and also provided a baseline for the solid Al samples tested. The main results from experiments were that the Young’s moduli (E) for porous Al samples (55.8% relative density) were 15.9-16.6 GPa depending on pore diameter, which is in good agreement with the CES EduPack predictions; while the compressive strengths (σc) were 155-185 MPa, higher than those predicted by CES EduPack. The results from the FEM simulations using 3D models (55.8% relative density) revealed the onset of yielding at 13.5-14.0 MPa, which correlates well with CES EduPack data. Overall results indicated that a combination of experiments and FEM simulations can be used to calculate structure-property relationships and to predict yielding and failure, which may help in the pursuit of simulation-based design of metallic foams. In the future, more robust modeling and simulation techniques will be explored, as well as investigating closed cell Al foams and different porous geometries (nm to micron). This study can help to improve the current methods of characterizing porous materials and enhance knowledge about their properties for alternative energy applications, while promoting their design through integrated approaches.

scholarly journals Evaluation of Effective Elastic, Piezoelectric, and Dielectric Properties of SU8/ZnO Nanocomposite for Vertically Integrated Nanogenerators Using Finite Element Method

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Neelam Mishra ◽  
Braj Krishna ◽  
Randhir Singh ◽  
Kaushik Das
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Material Properties ◽  
Volume Fraction ◽  
Dielectric Material ◽  
Mechanical Energy ◽  
Zno Nanowires ◽  
Piezoelectric Composite ◽  
Fem Simulations ◽  
Element Method

A nanogenerator is a nanodevice which converts ambient mechanical energy into electrical energy. A piezoelectric nanocomposite, composed of vertical arrays of piezoelectric zinc oxide (ZnO) nanowires, encapsulated in a compliant polymeric matrix, is one of most common configurations of a nanogenerator. Knowledge of the effective elastic, piezoelectric, and dielectric material properties of the piezoelectric nanocomposite is critical in the design of a nanogenerator. In this work, the effective material properties of a unidirectional, unimodal, continuous piezoelectric composite, consisting of SU8 photoresist as matrix and vertical array of ZnO nanowires as reinforcement, are systematically evaluated using finite element method (FEM). The FEM simulations were carried out on cubic representative volume elements (RVEs). Four different types of arrangements of ZnO nanowires and three sizes of RVEs have been considered. The volume fraction of ZnO nanowires is varied from 0 to a maximum of 0.7. Homogeneous displacement and electric potential are prescribed as boundary conditions. The material properties are evaluated as functions of reinforcement volume fraction. The values obtained through FEM simulations are compared with the results obtained via the Eshelby-Mori-Tanaka micromechanics. The results demonstrate the significant effects of ZnO arrangement, ZnO volume fraction, and size of RVE on the material properties.

DEM/FEM Simulations of Dynamic Response of Projectile Penetrating into Granular Medium

2016 ◽  
Vol 715 ◽  
pp. 167-173
Author(s):  
Shinnosuke Takeda ◽  
Kinya Ogawa ◽  
Kenichi Tanigaki ◽  
Keitaro Horikawa ◽  
Hidetoshi Kobayashi
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Granular Medium ◽  
Resistance Force ◽  
Projectile Velocity ◽  
Fem Simulations ◽  
Dem Simulations ◽  
Dynamic Penetration ◽  
Peak Value ◽  
Element Method

Dynamic elastic Finite Element Method (FEM) and Discrete element method (DEM) simulations are carried out to investigate dynamic penetration of a projectile into a target of granular medium. It was found that the highly densified region of granular medium was generated just ahead of the projectile and began to propagate spherically with much higher velocity than that of projectile which leaves relatively rarefied medium region. This propagation phenomenon was probably the result of a collision and momentum transfer between particles in target granular medium. The propagation velocity of the densified region decreased during penetration as depending not only on the packing ratio of target medium but also on the projectile velocity. The resistance force of projectile was also investigated in the case of penetration of projectiles with various body lengths. The resistance force increased rapidly and reached to the peak. The peak value was expressed in terms of momentum change of target particles. The resistance force decreased periodically after the peak value. The period clearly depended on the length of projectile. It is obvious that this was caused by the stress wave reverberations in the projectiles with various body lengths.

Piezoceramic Stack Actuators for Micropositioning Stage

2012 ◽  
Vol 512-515 ◽  
pp. 1337-1341
Author(s):  
Ya Nan Xu ◽  
Xiang Cheng Chu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Theoretical Analysis ◽  
Natural Frequency ◽  
Experimental Results ◽  
Flexure Hinge ◽  
Positioning Accuracy ◽  
Fem Simulations ◽  
Element Method

Based on piezoceramic stack actuators, a stage (dimension of 50mm×50mm×11mm) with a symmetric displacement magnifying mechanism is studied in this paper. FEM simulations are carried out to reveal the performance of the micropositioning stage and the amplification radio of the flexure hinge is 4.76. The working mode of the flexure hinge of the stage is also simulated by finite element method, and its natural frequency is 3291Hz. A series of tests about piezoceramic stack actuators have been done, including static, dynamic and temperature tests. The experimental results are identical to the theoretical analysis and give help to the application of piezoceramic stack actuators. It can also help the precise micropositioning stage driven by PZT to achieve higher positioning accuracy and resolution.

scholarly journals Finite Element Method Simulation and Characterization of a Thermal Flow Sensor Based on Printed Circuit Board Technology for Various Fluids

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 833 ◽  
Author(s):  
Thomas Glatzl ◽  
Roman Beigelbeck ◽  
Samir Cerimovic ◽  
Harald Steiner ◽  
Albert Treytl
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Printed Circuit Board ◽  
Flow Sensor ◽  
Circuit Board ◽  
Thermal Flow ◽  
Fem Simulations ◽  
Printed Circuit ◽  
Thermal Flow Sensor ◽  
Element Method

We present finite element method (FEM) simulations of a thermal flow sensor as well as a comparison to measurement results. The thermal sensor is purely based on printed circuit board (PCB) technology, designed for heating, ventilation, and air conditioning (HVAC) systems. Design and readout method of the sensor enables the possibility to measure the flow velocity in various fluids. 2D-FEM simulations were carried out in order to predict the sensor characteristic of envisaged setups. The simulations enable a fast and easy way to evaluate the sensor’s behaviour in different fluids. The results of the FEM simulations are compared to measurements in a real environment, proving the credibility of the model.

scholarly journals Modelling the conduction mechanisms in low density polyethylene material using finite element method

2021 ◽  
Vol 63 (1) ◽  
pp. 27-33
Author(s):  
Mai Quyen Hoang ◽  
◽  
Thi Thu Nga Vu ◽  
Manh Quan Nguyen ◽  
Severine Le Roy ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Charge Transport ◽  
Transport Model ◽  
Polymer Materials ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Original Design ◽  
Conduction Mechanisms ◽  
Element Method

Polymers used as insulating materials are increasingly popular in many different fields. In electrical engineering - electronics, polymers are used in high-voltage transmission cables, capacitors, transformers, or as part of an embedded system in the IGBT module thanks to its superior thermal and electrical insulation properties. One of the disadvantages of polymers is the possible accumulation of space charge in the material volume for a long time, leading to an increase in the electric field compared to the original design value. Charge transport models in polymer materials have been increasingly developed to predict the conduction mechanisms under thermal-electrical stress. In this study, from a finite volume method (FVM), the authors developed a charge transport model in low density polyethylene (LDPE) based on the finite element method (FEM). The simulation results of this model are also compared to experimental results and to the FVM model under different electric fields for LDPE.

scholarly journals The influence of selected factors on the load capacity of sewers that are renovated using the relining method

2018 ◽  
Vol 45 ◽  
pp. 00057
Author(s):  
Beata Nienartowicz
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Computer Simulations ◽  
Load Capacity ◽  
Laboratory Research ◽  
The Finite Element Method ◽  
Fem Simulations ◽  
Lengthy Analysis ◽  
Element Method

The paper contains the results of a lengthy analysis of the operation of sewers renovated using the relining method. The author based the analysis on the effects obtained from computer simulations that were carried out using the Finite Element Method. The models used to proceed with the FEM simulations were verified by the results obtained from 1:1 laboratory research, conducted by the author over the period 2011-2013. The influence of a few strictly defined factors, related to the cooperation between the liner, injection grout and the construction of the original pipe, were taken into consideration. The report contains the description of FEM simulations and their assumptions, as well as a synthetic analysis of the results.

Simulation of tuning graphene plasmonic behaviors by ferroelectric domains for self-driven infrared photodetector applications

Nanoscale ◽  
2019 ◽  
Vol 11 (43) ◽  
pp. 20868-20875 ◽  
Author(s):  
Junxiong Guo ◽  
Yu Liu ◽  
Yuan Lin ◽  
Yu Tian ◽  
Jinxing Zhang ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Interfacial Effect ◽  
Infrared Photodetector ◽  
The Finite Element Method ◽  
Ferroelectric Domains ◽  
Element Method

We propose a graphene plasmonic infrared photodetector tuned by ferroelectric domains and investigate the interfacial effect using the finite element method.

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