Field Of Finite Element Analysis Research Articles

A strain field reconstruction method based on digital twin considering real-time loading deviations from intended test

For the static loading test, digital twin (DT) constructed by multi-type data fusion can combine the advantages of these data, which has potential application in test monitoring. Affected by assembly and manufacturing defects of test system, the loading deviations are difficult to avoid and quantify, and it has an important effect on the strain state of structures. However, the current DT is built by data fusion of strain gauges data and strain field of finite element analysis (FEA) only, and how to build DT considering real-time loading deviations by fusing multi-type sensor data remains a challenging task. Therefore, a strain field reconstruction method based on DT considering the real-time loading deviations (DT-SFRM-LD) is proposed to improve the accuracy of DT. In the test, the loading deviations calculated by displacement sensors data are used as FEA database input to obtain FEA strain field considering real-time loading deviations. The FEA strain field is combined with strain gauges data to construct DT in real time, which combines all the multi-type data advantages of displacement gauges, FEA strain field and strain gauges. A cylindrical shell test is performed to validate the high accuracy of DT-SFRM-LD. Results indicate that the AvgErr (5.0%) and MaxErr (13.6%) of DT-SFRM-LD are 4.3% and 10.0% lower than those of conventional DT method, and the AvgErr of DT-SFRM-LD is less affected by the eccentricity distance. In general, under different test conditions, the accuracy of DT-SFRM-LD is always higher than that of conventional DT method, indicating that considering the real-time loading deviations by displacement gauges is helpful to provide accurate FEA strain field distribution and to improve the accuracy of DT-SFRM-LD.

A general quadratic enrichment of the Crouzeix–Raviart finite element

The Crouzeix–Raviart finite element method is widely recognized in the field of finite element analysis due to its nonconforming nature. The main goal of this paper is to present a general strategy for enhancing the Crouzeix–Raviart finite element using quadratic polynomial functions and three additional general degrees of freedom. To achieve this, we present a characterization result on the enriched degrees of freedom, enabling to define a new enriched finite element. This general approach is employed to introduce two distinct admissible families of enriched degrees of freedom. Numerical results demonstrate an enhancement in the accuracy of the proposed method when compared to the standard Crouzeix–Raviart finite element, confirming the effectiveness of the proposed enrichment strategy.

DESIGN AND ANALYSIS OF PRESSURE VESSEL USING DIFFERENT MATERIALS

This project explores the field of Finite Element Analysis (FEA) in relation to pressure vessels that have different head configurations, while ensuring that the cylindrical volume and thickness remain uniform. The project adheres to ASME standards, specifically Section VIII, Division I, and focuses on designing a pressure vessel that can withstand a pressure of 8 bar within a volume of 24 liters. The main objective of using FEA is to identify areas of stress concentration in each head design. In industrial settings, pressure vessels play a crucial role in containing fluids or gases under varying pressures. The choice of head configuration significantly impacts the distribution of stress and the overall structural strength. This project specifically utilizes ANSYS software for static and thermal analyses to compare stress distribution in pressure vessels with flat heads, elliptical heads, and other common head designs. The goal is to identify configurations that exhibit lower stress levels, with a particular emphasis on practical scenarios that favor elliptical heads. Additionally, the project explores finite element modeling techniques to evaluate pressure vessels made from different materials such as Nimonic 80A and SA516 Gr70 under high-stress conditions

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.

Guaranteed-quality higher-order triangular meshing of 2D domains

We present a guaranteed quality mesh generation algorithm for the curvilinear triangulation of planar domains with piecewise polynomial boundary. The resulting mesh consists of higher-order triangular elements which are not only regular (i.e., with injective geometric map) but respect strict bounds on quality measures like scaled Jacobian and MIPS distortion. This also implies that the curved triangles' inner angles are bounded from above and below. These are key quality criteria, for instance, in the field of finite element analysis. The domain boundary is reproduced exactly, without geometric approximation error. The central idea is to transform the curvilinear meshing problem into a linear meshing problem via a carefully constructed transformation of bounded distortion, enabling us to leverage key results on guaranteed-quality straight-edge triangulation. The transformation is based on a simple yet general construction and observations about convergence properties of curves under subdivision. Our algorithm can handle arbitrary polynomial order, arbitrarily sharp corners, feature and interface curves, and can be executed using rational arithmetic for strict reliability.

2D Finite Element Thermo-Mechanical Model To Predict Machining Induced Residual Stresses Using ALE Approach

Understanding the machining process in the microscopic level has been a challenge over the years. Machining process as such is very complex due to various factors, which is involved like friction, plastic deformation, material failure etc. The present works aims at developing a 2D FE model to predict the residual stresses induced after machining operation. Over the years’ lot of development has taken place particularly with the advent of high-end computers and FEM software packages. This works aims at incorporating the developments that has taken place in the field of Finite Element Analysis of machining processes and try to give an improvised model to understand the machining process in a better way. The work also aims at determining the residual stresses that are induced in the material after machining, its nature and magnitude. The influence of machining parameters on the machining induced residual stresses was studied with the help of commercially available software. Present work has been conducted on AISI 1045 steel. Simulations results are in good agreement with the experimental results.

A new Delaunay triangulation algorithm based on constrained maximum circumscribed circle

Delaunay triangulation is gradually playing an important role in the field of finite element analysis, image recognition, and medical visualization. Considering the quality and partition efficiency, a new Delaunay triangulation method based on constrained maximum circumscribed circle is proposed. First, according to two important criteria, the empty circle features and the maximized minimum angle characteristics, we established constrained conditions. Then, we iterated the container vertices, structure triangular face linked lists, and finally got the Delaunay data. The experimental results showed that the efficiency of the improved triangulation dissection method increased by 9.47% compared with traditional triangulation algorithms in irregular triangle vertex data.

Influence of Blast Wave on Behavior of Steel Plate

The threat of terrorism has led to increased awareness about protecting properties from damage in terrorist attacks. With the rapid growth of the computer industry and progress in the field of finite-element analysis, evaluations of conventional weapons focus more on simulations than on experiments. There are many approaches to simulate blast and impact. These include Eulerian, Lagrangian, multi-material arbitrary Lagrangian-Eulerian (MM-ALE), and the meshless approach of smooth particle hydrodynamics (SPH) methods. Each method has distinct advantages. In this study, finite-element analysis was applied to simulate a 1 kg trinitrotoluene (TNT) blast in front of a 20-mm-thick steel plate. Three different approaches were simulated: Eulerian, MM-ALE, and SPH. Each method gave different results for the von Mises stress distribution, peak pressure, and displacement of the steel plate. A comparison of the three results implies that using one of these three approaches may generate a significant blast simulation.

Semi-automated segmentation and visualisation of outer bone cortex from medical images

Good segmentation of the outer bone cortex from medical images is a prerequisite for applications in the field of finite element analysis, surgical planning environments and personalised, case dependent, bone reconstruction. However, current segmentation procedures are often unsatisfactory. This study presents an automated filter procedure to generate a set of adapted contours from which a surface mesh can be deduced directly. The degree of interaction is user determined. The bone contours are extracted from the patients CT data by quick grey value segmentation. An extended filter procedure then only retains contour information representing the outer cortex as more specific internal loops and shape irregularities are removed, tailoring the image for the above-mentioned applications. The developed medical image based design methodology to convert contour sets of multiple bone types, from tibia tumour to neurocranium, is reported and discussed.

Computer aided design education—The the more the education, the less the use

The use of computers does not at present fit comfortably into the world of the design engineer. To improve this situation, it is not the engineer but the computer that needs educating. The use of CAD requires a database combined with an engineering editor to allow evolutionary design. In the field of finite element analysis, CAD promises to save money while restoring the engineer to his proper position.