Use Of Finite Element Analysis Research Articles

Modeling elastic properties of biocomposites using various analytical models and ansys material designer

A major focus of emerging research is the design and development of new materials for future industries in order to replace older ones in an environment-friendly way. Composite material is one of them, especially biocomposites. Over the past few decades, there is a lot of advancement in developing composite materials. We can see the applications of composite materials are increasing day by day in aerospace, automotive, medical, and construction field. Generally, the properties of unidirectional composites are evaluated by analytical methods or by Finite element Method. We present here a study of the properties of unidirectional biocomposite by using Ansys Material Designer and compare them with analytical methods including Rule of mixtures (ROM), Modified Rule of mixtures (MROM), Halpin-Tsai, Chamis, and Elasticity Approach models. The use of finite element analysis requires rigorous analysis of representative volume element (RVE), results strongly depend on the loading and boundary conditions we applied. So it is a cumbersome task to find out the elastic constants of composites. Hence, we used Ansys material designer, which is the easiest and quickest way of modeling composites. It is also possible to model various RVEs like square, hexagonal, and diamond. The results obtained by analytical methods and Ansys material designer are compared through graphs and the explanation is provided for each deviation in the properties. The results show great accuracy as compared with analytical methods. Only the Transverse elastic modulus (E22) and in-plane shear modulus (G12) show slight variation in properties. As we got accurate results, we also proposed properties for Random unidirectional, Woven, and Chopped fiber composites also by using Ansys material designer.

Pathoanatomy, biomechanics, and treatment of upper cervical ligamentous instability: A literature review.

Cervical spine instability broadly refers to compromise of the articular congruity. It can be stratified according to spinal level, functional compromise, and mechanism of instability. Conventional wisdom advocates for use of bracing and physical therapy with only a subset of patients proceeding to obtain surgical treatment. The purpose of this review article is to summarize the current state of knowledge on upper cervical ligamentous instability. The literature search was performed in Mendeley. Search fields were varied until redundant. All articles were screened by title and abstract and a preliminary decision to include an article was made. The full-text screening was performed on the selected articles. Any question regarding the inclusion of an article was discussed by 3 authors until an agreement was reached. Many articles report on the etiological factors including ligamentous laxity, traumatic injury, syndrome instability, iatrogenic instability, congenital, and inflammatory causes. A few recent studies elucidate new findings regarding pathoanatomy through the use of finite element analysis. A few articles demonstrate the diagnosis and show that radiographs alone have a low diagnostic rate and that functional MRI may be able to better quantify instability. Conservative treatment has been described, but there are no outcome studies in the literature. Surgical treatment has been described in many different populations with good radiologic and clinical outcomes. Recently the use of preoperative 3D CT reconstruction has been described with radiographic and immediate postoperative patient-reported outcomes. The presentation of upper cervical spinal instability can be asymptomatic, symptoms of isolated instability, symptoms of nerve irritation, vertebrobasilar insufficiency, or severe neurologic compromise. 3D fine element analysis models and motion-capture systems have the potential to increase our understanding of the pathoanatomic cascade in both traumatic and non-traumatic cases of upper cervical spinal instability. A few modalities on the horizon could increase diagnostic potential. More efforts are needed regarding the use of fine element analysis in understanding the pathoanatomic cascade, the long-term outcomes of children over a spectrum of syndromic causes, and the potential of preoperative virtual simulation to improve surgical outcomes.

Bioengineering Tools Applied to Dentistry: Validation Methods for In Vitro and In Silico Analysis.

This study aimed to evaluate the use of bioengineering tools, finite element analysis, strain gauge analysis, photoelastic analysis, and digital image correlation, in computational studies with greater validity and reproducibility. A bibliographic search was performed in the main health databases PUBMED and Scholar Google, in which different studies, among them, laboratory studies, case reports, systematic reviews, and literature reviews, which were developed in living individuals, were included. Therefore, articles that did not deal with the use of finite element analysis, strain gauge analysis, photoelastic analysis, and digital image correlation were excluded, as well as their use in computational studies with greater validity and reproducibility. According to the methodological analysis, it is observed that the average publication of articles in the Pubmed database was 2.03 and with a standard deviation of 1.89. While in Google Scholar, the average was 0.78 and the standard deviation was 0.90. Thus, it is possible to verify that there was a significant variation in the number of articles in the two databases. Modern dentistry finds in finite element analysis, strain gauge, photoelastic and digital image correlation a way to analyze the biomechanical behavior in dental materials to obtain results that assist to obtain rehabilitations with favorable prognosis and patient satisfaction.

Corrective Mechanism Aftermath Surgical Treatment of Spine Deformity due to Scoliosis: A Systematic Review of Finite Element Studies.

This paper presents a systematic study in reviewing the application of finite element method for the analysis of correction mechanism of spine deformity due to scoliosis. The study is aimed at systematically (1) reviewing the use of finite element analysis in spine deformity case, (2) reviewing the modelling of pedicle screw and rod system in scoliosis surgery, and (3) analysing and discussing gap between the studies. Using the restricted key phrases, the review gathered studies from 2001 to 2021 from various electronic databases (Scopus, ScienceDirect, PubMed, Medline, and WorldCAT). Studies were included if they reported a finite element study on spine deformity. Studies that did not fully disclose their methodology and results had significant discrepancies, not published in English or not yet published were all disqualified. Regardless of inconsistencies in the methodological design of the studies, the quality of all papers was above the acceptable level. A total of fifteen manuscripts were considered for inclusion and were given a comprehensive review. This study indicates that analysing the forces acting on the spine, as well as the interrelationship between the force, stress, and degree of correction (which measured as the Cobb angle), could help to improve the corrective mechanism procedure of spine deformity. Pedicle screws and its placement strategies are also important as it influence the corrective forces for scoliosis treatment. Hence, the findings of this study could potentially be used as a guidance to develop a reliable finite element analysis that can predict the biomechanics responses during the corrective spine deformity treatment.

Experimental and Numerical Investigations of Cement Bonding Properties at Elevated Temperatures-The Effect of Sample Cooling.

Well integrity is currently defined through the concept of well barriers, in which one or more barriers are used to prevent unwanted fluid flow. Many papers have highlighted that the casing–cement interfacial bonding is critical for well integrity, but many discrepancies between laboratory experiments and field data have been noticed. The use of finite element analysis is now established as an alternative to complex in situ tests, but these simulations are sensitive to the input parameters, which results in many discrepancies across published works. Currently, the cohesive zone material (CZM) method is considered to offer good results if the correct parameters are selected or experimentally determined. The novelty of this paper lies in the development of a better workflow that enables the simulation of three processes that are acting on the laboratory-scale casing–cement system: temperature changes, debonding, and post-debonding behavior. The aim of this paper is to fully understand the debonding process within laboratory-scale samples, and thus to eventually enable upscaling in the near future. The paper presents a new workflow generated using FEM that allows us to determine the contact stresses at the casing–cement interface during temperature changes at the moment of debonding and post-debonding. The results presented within this paper show that temperature samples tested according to the push-down setup will provide similar interfacial bonding shear strength values; however, post-debonding, there is a remaining frictional force slightly higher than that of the room-temperature samples. In this case, the results are within a 5% error of the average field data, which is slightly higher than in our previous experiments, where only room temperature data were considered. A major outcome of our paper is the demonstration of the existence of friction forces after debonding, which are a result of radial stresses induced during the debonding process.

Performing a Three-Dimensional Finite Element Analysis to Simulate and Quantify the Contact Pressure in the Canine Elbow Joint: A Pilot Study.

The aim of this study was to measure surface pressures and force distribution on radius and ulna in healthy and dysplastic elbow joints in different positions using the finite element analysis (FEA). FEA was performed on computed tomographic data of healthy and fragmented coronoid process diseased elbow joints of Labrador Retrievers. It considered the articular cartilage, collateral ligaments, triceps and biceps muscle. The analysis of each joint was performed in four positions (standing position: 145 degrees and three positions of the stance phase of gait: beginning: 115 degrees, middle: 110 degrees, end: 145 degrees joint angle) in consideration of different ground reaction forces (standing: 88.3 N; stance phase of gait: 182.5 N). Mean values of total force of 317.5 N (standing), 590.7 N (beginning), 330.9 N (middle) and 730.9 N (end) were measured. The percentual force distribution resulted in a total of 49.56 ± 26.58% on the ulna with a very inhomogeneous distribution. A significant difference was detected between the positions 'standing' and 'end' (p = 0.0497) regardless of the joint condition. In some FEA results, visual assessment of the surface pressures indicated an increase in pressure in the region of the medial compartment without a uniform pattern. An increase in pressure resulted in an area increase in the pressure marks on the joint surface and measurable pressure was increased at a larger joint angle. FEA can provide information about the transmission of force in the joint. Prior to the use of FEA in scientific clinical research for the simulation of force, further model improvements are necessary.

КОНЕЧНО-ЭЛЕМЕНТНЫЙ АНАЛИЗ ИМПЛАНТАТОВ СИСТЕМЫ HUMANA DENTAL С ИННОВАЦИОННОЙ ПОВЕРХНОСТЬЮ И ДИЗАЙНОМ РЕЗЬБЫ ДЛЯ ВЫЯВЛЕНИЯ РАСПРЕДЕЛЕНИЯ НАПРЯЖЕНИЙ В ИМПЛАНТАТЕ, КОСТНОЙ ТКАНИ И В СОЕДИНЕНИИ АБАТМЕНТ – ИМПЛАНТАТ – КОСТЬ

This article presents the results of mathematical modeling of the stress-strain state of the finite element analysis of the justification for the use of Humana Dental implants with an innovative surface microstructure and thread design parameters during dental implantation. As a result of the study, after placing the implants in the created three-dimensional model, consisting of trabecular and cortical bones, it was revealed that the angle of implant placement significantly affects the distribution of stress in the bone. The rough, well-structured surface improves the contact of the implant with the bone. The stress distribution on dental implants with different geometry and thread design was revealed, and the most effective thread parameters for uniform load distribution were determined.
 Aim. Substantiation of the use of Humana Dental implants with innovative macro-microstructure of the surface and thread design parameters during dental implantation in various clinical situations.
 Material and methods. Samples of BioSink and Vega implants from Humana Dental were studied to assess the stress distribution by mathematical modeling of the stress-strain state in the cortical and spongy bone surrounding two models of implants with a diameter of 4.2 mm and a length of 11.5 mm, as well as with a different thread shape design. The implants were installed in the created three-dimensional model strictly vertically and at an angle of 30°. Geometric models were built in CAD Catia V5, the calculation was carried out in the software package Ansys R19.2.
 Resalts. As a result of the study, it was revealed that in all cases the maximum concentration of stresses falls on the cortical layer of bone near contact with the implant, and in the spongy bone with vertical installation, maximum stresses in all cases are reached near the lower part of the implant. The peak voltage in the cortical bone was highest in the threaded part of the implants. When changing the angle of installation of the implant, the maximum voltages can increase many times, but when changing the thread pitch, only small fluctuations in voltages are noted, which do not fit into any trend. In the peri-implant region, the cortical bone showed a higher concentration of tension than the spongy bone.
 Conclusions. The use of finite element analysis made it possible to identify the stress distribution on dental implants with different thread geometries and designs and to determine the most effective thread parameters for uniform load distribution.

Investigations of Middle-Caliber Anti-Aircraft Cannon Interior Ballistics including Heat Transfer Problem in Estimation of Critical Burst Length

Numerical and experimental investigations of armament systems are an important part of modern design processes. The presented paper reports problems that were encountered on the theoretical analysis of the performance of 35 mm anti-aircraft cannon and the way in which they were solved. The first problem concerns the application of results of closed vessel tests of used propellant in interior ballistics simulations. The use of a nonstandard form of the gas generation rate equation solved this problem. The second problem concerned the assessment of projectile–barrel interaction. The barrel resistance was estimated making use of finite element analysis. The third problem arose from the need to determine the heat transfer from propellant gases to the barrel. The employed formula for the heat exchange coefficient and 2D modelling of the heat conduction in the barrel provided the solution. Selected elements of the theoretical model were validated by shooting range experiments and data provided by the ammunition producer. Using the considered approach, crucial ballistic parameters (maximum propellant gas pressure and muzzle velocity) were estimated with an error of less than 6.0%, without application of additional fitting coefficients. The numerical estimation of the barrel external surface temperature provided a relative discrepancy with the experimental data lower than 6% and enabled the estimation of the critical burst length, equal to 14 shots.

Computational investigation of the post-yielding behavior of 3D-printed polymer lattice structures

Abstract Sandwich structures are widely used due to their light weight, high specific strength, and high specific energy absorption. Three-dimensional (3D) printing has recently been explored for creating the lattice cores of these sandwich structures. Experimental evaluation of the mechanical response of lattice cell structures (LCSs) is expensive in time and materials. As such, the finite element analysis (FEA) can be used to predict the mechanical behavior of LCSs with many different design variations more economically. Though there have been several reports on the use of FEA to develop models for predicting the post-yielding stages of 3D-printed LCSs, they are still insufficient to be a more general purpose due to the limitations associated with the lattice prediction behavior of specific features, certain geometries, and common materials along with showing sometimes poor prediction due to the computationally cheap elements out of which these models have been composed in most cases. This study focuses on the response of different LCSs at post-yielding stages based on the hexahedral elements to capture accurately the behaviors of 3D-printed polymeric lattices made of the Acrylonitrile Butadiene Styrene material. For this reason, three types of lattices such as body centered cubic, tetrahedron with horizontal struts, and pyramidal are considered. The FEA models are developed to capture the post-yielding compressive behavior of these different LCSs. These models are used to understand and provide detailed information of the failure mechanisms and relation between post-yielding deformations and the topologies of the lattice. All of these configurations were tested before experimentally during compression in the z-direction under quasi-static conditions and are compared here with the FEA results. The post-yielding behavior obtained from FEA matches reasonably well with the experimental observations, providing the validity of the FEA models.

A methodology to integrate process-induced subsurface characteristics into a digital twin-based framework for the evaluation of machining processes

The consideration of process-induced subsurface characteristics as an essential quality parameter of manufactured components is of primary relevance. An established means for the prediction of these characteristics such as residual stress, hardness or phase transformations is the use of finite element analysis, which can be used to model changes in the material for defined process configurations and engagement scenarios. However, due to high simulation times and in many cases limited model sizes, only selected scenarios can be evaluated. Process simulation systems which model the cutting process using empirical models and geometric representations of the tool and workpiece to predict the process forces and, e.g., deflections, offer the possibility to simulate entire machining processes efficiently. In this contribution, a methodology is presented to integrate process-induced alterations of the subsurface during milling into the workpiece model of a process simulation system. For the evaluation of these alterations, finite element analyses can be used for representative engagement and process scenarios, which have to be selected a priori based on each process. By extending the digital-twin of the workpiece with this information, the influence of complex machining operations with time-variant engagement conditions can be evaluated continuously. As a result, the presented framework thus provides a basis for predicting the resulting quality of the manufactured component with respect to subsurface characteristics.

A direct methodology for the calibration of ductile damage models from a simple multiaxial test

In the present work a straightforward calibration procedure of ductile damage models is proposed. The direct methodology involves the use of a simple multiaxial specimen, to be tested with a universal testing machine, capable to reproduce different stress states in the material. The specimen geometry was the one proposed by Driemeier et al. [1]. In addition, a numerical-analytical procedure was devised for the identification of material strains to fracture and corresponding stress states, directly from experimental tests. This allowed to overcome the use of Finite Element Analysis and inverse methods usually adopted to retrieve the local parameters representative of the material ductility.

Biomechanical Analysis of Human Femur using Finite Element Method: A Review Study

This review paper is an attempt to take up all the research work of the various researchers during the last decades in the field of finite element analysis of the human femur bone using various techniques. To do this, we have studied several articles that have been published by renowned publishers and produced an inclusive report. Biomechanics is an interdisciplinary field, where concepts from physics are used to solve various problems of health science.In the last three decades, the use of finite element analysis in the area of biomechanics to understand the behavior of human hard tissues has been increased significantly; especially bones in the relation to force distribution, fracture pattern, and their predictions, assignment of mechanical properties, and implant (prostheses) design, etc. This review article presents a comprehensive study of the analysis of femur bone analysis using the finite element to help researchers and healthcare professionals efficiently cure patients by identifying fracture risk criteria and improved the design of human implants for society.

Finite Element Analysis of Biomechanical Behaviour of Remaining Coronal Dentin in Endodontically Restored Tooth - A Systematic Review [Evaluation of Stress Distribution in FEA Studies

Background: Since few years finite element (FE) analysis has turn out to be a widespread tool for investigators seeking to simulate the tooth biomechanics and associated structures. Finite element method plays important role to expand understanding of the ferrule effect. This paper contains a systematic review and conclusions from FE method grounded computational simulations of the the tooth with post and core to simulate function and tissue behavior
 Methods: 14 applicable papers were linked within this systematic literature search. Uprooted data contained information on type of tooth, location of tooth, magnitude of force, software used for modelling, boundary condition, method of scanning, validation, tooth with ferrule, tooth without ferrule, key findings.
 Results: Included papers illustrated use of FE analysis for replication of including nonlinear tooth and tissue mechanics, contact analysis and rigid body movements. We executed multi-database systematic review through PRISMA standards accomplishing inclusion criteria and results were investigated and précised for appropriate papers.
 Discussion: With prompt expansions of computer knowledge, the FEA now recognized as a potent method in dental biomechanics due to its flexibility in measuring stress dispersals within multidimensional structures. The researcher will be well equipped to understand the results of FEA investigations and correlate these results to clinical settings after learning the basic theory, application, method, and limitations of FEA in dentistry. Ferrule has a precarious impact on stress reduction. Teeth are less stressed when posts and cores are composed of strong materials. Keeping supragingival tooth structure included within the crown gives repaired teeth extraordinary strength.

A new protocol to accurately track long–term orthodontic tooth movement and support patient-specific numerical modeling

Numerical simulation of long-term orthodontic tooth movement based on Finite Element Analysis (FEA) could help clinicians to plan more efficient and mechanically sound treatments. However, most of FEA studies assume idealized loading conditions and lack experimental calibration or validation. The goal of this paper is to propose a novel clinical protocol to accurately track orthodontic tooth displacement in three-dimensions (3D) and provide 3D models that may support FEA. Our protocol uses an initial cone beam computed tomography (CBCT) scan and several intra-oral scans (IOS) to generate 3D models of the maxillary bone and teeth ready for use in FEA. The protocol was applied to monitor the canine retraction of a patient during seven months. A second CBCT scan was performed at the end of the study for validation purposes. In order to ease FEA, a frictionless and statically determinate lingual device for maxillary canine retraction was designed. Numerical simulations were set up using the 3D models provided by our protocol to show the relevance of our proposal. Comparison of numerical and clinical results highlights the suitability of this protocol to support patient-specific FEA.

Finite elements analysis suggests a defensive role for osteoderms in titanosaur dinosaurs (Sauropoda)

Here we present, for the first time, the use of finite element analysis to evaluate bites of two possible predators, a baurusuchid crocodyliform and an abelisaurid theropod into titanosaur osteoderms, in order to test if these structures could act as defensive tools. Our results showed that bites caused much less stress on osteoderms that did not went through internal resorption and were composed mainly by solid bone. Our data strengths the hypothesis that titanosaur osteoderms could have provided more functions than just mineral storage.

Modelling and Finite Element Analysis of an Aircraft Wing using Composite Laminates

The use of finite element analysis is increasingly gaining popularity in the design and analysis of aircraft structures. Also, composite materials in the manufacturing and design of aircraft structures are increasing due to their exceptional properties of high stiffness to weight ratio. Applications include Composite structures are made up of laminates with different fibre orientations, which adversely affects the property of the composites formed. For this study, the three main parts of the aircraft wing are considered for designing: the spars, the ribs, and the aircraft’s skin. The spars and made up of aluminium alloy, and the ribs are made up of structural steel. Two different wing models are designed. For Model 1, the skin is assigned Titanium alloy as a material, and for Model 2, CFRP (Carbon Fibre Reinforced Polymer) with resin epoxy is used as the skin material. The ribs are made of structural steel and the spars of titanium alloy for both models. This paper aims to compare the materials mentioned above to find the optimum strength to weight ratio. It was found that, for a given uniform load on the bottom of the aircraft’s skin, a weight reduction of 2.37 % was observed in favour of Model 2, the deformation was reduced by 51 per cent, and the von-Mises stress was reduced by ≈ 85%. This paper’s results can be used in manufacturing structural components of UAV, especially the wings due to lighter weight and more flexibility and durability than standard titanium alloys and the significant role played by the orientation of the plies in deciding the strength of the composite.

Artificial intelligence approach for increasing the fidelity of the second order fibre orientation tensor for use in finite element analysis

A more efficient integrated computational approach for the design of injection and compression moulded composites which maps the results of manufacturing simulations as input to structural simulations is proposed. This methodology overcomes the limitations caused by insufficient detail provided by the second order fibre orientation tensor (FOT) output from manufacturing simulations which are needed in advanced structural finite element models that incorporate damage and failure. An artificial neural network (ANN) framework is proposed to predict a fibre orientation distribution function (ODF) from the FOT. The ANN contains the equation for calculating the FOT from the ODF such that the ODF is optimized to reproduce the input FOT. It is shown that the proposed framework is nearly as accurate as using experimentally measured ODF for predicting the stress strain response and failure of a compression moulded composite.

CoreValve vs. Sapien 3 Transcatheter Aortic Valve Replacement: A Finite Element Analysis Study

Aim: to investigate the factors implied in the development of postoperative complications in both self-expandable and balloon-expandable transcatheter heart valves by means of finite element analysis (FEA). Materials and methods: FEA was integrated into CT scans to investigate two cases of postoperative device failure for valve thrombosis after the successful implantation of a CoreValve and a Sapien 3 valve. Data were then compared with two patients who had undergone uncomplicated transcatheter heart valve replacement (TAVR) with the same types of valves. Results: Computational biomechanical modeling showed calcifications persisting after device expansion, not visible on the CT scan. These calcifications determined geometrical distortion and elliptical deformation of the valve predisposing to hemodynamic disturbances and potential thrombosis. Increased regional stress was also identified in correspondence to the areas of distortion with the associated paravalvular leak. Conclusion: the use of FEA as an adjunct to preoperative imaging might assist patient selection and procedure planning as well as help in the detection and prevention of TAVR complications.

Experimental Evaluation of True Stress-Strain for Ductile Thermoplastics

<div class="section abstract"><div class="htmlview paragraph">Thermoplastics find application in many automotive components. Off late, hardware testing is supplemented by analysis using finite element (FE) codes. One of the factors determining the analysis accuracy is the representation of the components with suitable material models. While a uniaxial tensile test on the specimens typically provides engineering stress-strain data, material plasticity models in commercial FE solvers, such as LS-DYNA and ABAQUS, require equivalent plastic strain versus true stress as input. Engineering stress and strain can be converted to the corresponding true stress and true strain using equations based on the constant volume assumption; however, these equations are valid only up to the point of necking. A conventional approach of estimating the true stress and true strain beyond necking involves a trial and error method in which several true stress-strain curves are generated, and a finite element simulation is used to find the best possible fit with the test data. This approach is time consuming and provides an approximate true stress-strain curve beyond necking. The objective of this paper is to provide an experimental alternative to the conventional approach. Digital image correlation (DIC) was used to measure volumetric strain in the necking region of a tensile test specimen by employing two cameras simultaneously, one focusing on the front (width, length) and the other focusing on the side (thickness, length) surface of the test specimen. True strain measured by DIC in the longitudinal direction and the true stress, estimated from the applied force and measured true transverse strains, were used to generate material models for use in FE analysis without modification, i.e. without a need for correction factors. Material models were then validated by comparing the FE simulation with the tensile test results.</div></div>

Simulating wave propagation in acoustic metamaterials with isogeometric analysis

Finite element analysis (FEA) is commonly used to simulate and design acoustic metamaterials (AMM). Numerical studies employing FEA often rely on Bloch-Floquet analysis of a single unit cell or direct numerical simulations that include many unit cells. Unfortunately, AMM unit cells with fine features necessitate dense computational meshes to resolve the geometry and accurately model wave motion, sometimes prohibiting the use of FEA. Isogeometric Analysis (IGA) is a potential alternative approach to FEA for wave propagation problems. IGA utilizes basis functions that are typically employed in Computer Aided Design (CAD) software, such as B-splines and Non-Uniform Rational B-Splines (NURBS), to represent both the geometry and the wave solution. The direct utilization of the CAD geometry eliminates the need for a separate computational mesh of the geometry and the smoothness of the NURBS basis functions provides increased accuracy per degree of freedom. The latter point is particularly useful for high frequency problems. This talk presents IGA as a means to model AMM behavior and compares results with FEA simulations in terms of total simulation time and accuracy. Finally, we comment on the current limitations of IGA and discuss avenues of future research. [Work supported by the ARL:UT postdoctoral fellowship program.]