Coupling Finite Element and Mesh-free Methods for Modelling Brain Deformation in Response to Tumour Growth

Very little is known about the deformation effects of tumour growth within the brain. Computer simulations have the potential to calculate such deformations. A method for computing localised high deformations within the brain’s soft tissue is presented. Such knowledge would be significant towards neuroscience and neurosurgery, particularly for quantifying tumour aggressiveness, therapy planning, as well as surgical planning and simulation. A Finite Element mesh used in the vicinity of a growing tumour is very quickly destroyed and cannot be used reliably unless complicated automatic re-meshing exists. Mesh-free methods are capable of handling much larger deformations, however are known to be less reliable that Finite Element analysis for moderate deformations. A mixed-mesh approach utilises mesh-free regions within localised high-deformation zones, with the remaining model comprised of a Finite Element mesh. In this study, a new algorithm is proposed coupling the Finite Element and Element Free Galerkin methods for use in applications of high localised deformation, such as brain tumour growth. The algorithm is verified against a number of separate Finite Element and mesh-free problems solved via validated/commercial software. Maximum errors of less than 0.85 mm were maintained, corresponding to the working resolution of an MRI scan. A mixed-mesh brain model is analysed with respect to different tumour growth volumes located behind the left ventricle. Significant displacements of up to 9.66 mm surrounding a 4118 mm3 sized tumour are noted, with 14.5% of the brain mesh suffering deformation greater than 5 mm.

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Finite Element Mesh Generator Applying Constraints’ Propagation and Isoparametric Mapping

ASME 1991 Computers in Engineering Conference: Volume 2 — Finite Elements/Computational Geometry; Computers in Education; Robotics and Controls ◽

10.1115/cie1991-0122 ◽

1991 ◽

Author(s):

J. Rodriguez ◽

M. Him

Keyword(s):

Finite Element ◽

Mesh Generation ◽

Element Model ◽

Finite Element Mesh ◽

Fe Model ◽

Element Analysis ◽

Element Mesh ◽

Mesh Generator ◽

Generation Algorithm ◽

Essential Input

Abstract This paper presents a finite element mesh generation algorithm (PREPAT) designed to automatically discretize two-dimensional domains. The mesh generation algorithm is a mapping scheme which creates a uniform isoparametric FE model based on a pre-partitioned domain of the component. The proposed algorithm provides a faster and more accurate tool in the pre-processing phase of a Finite Element Analysis (FEA). A primary goal of the developed mesh generator is to create a finite element model requiring only essential input from the analyst. As a result, the generator code utilizes only a sketch, based on geometric primitives, and information relating to loading/boundary conditions. These conditions represents the constraints that are propagated throughout the model and the available finite elements are uniformly mapped in the resulting sub-domains. Relative advantages and limitations of the mesh generator are discussed. Examples are presented to illustrate the accuracy, efficiency and applicability of PREPAT.

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Evolutionarily Coupled Finite-Element Mesh-Free Formulation for Modeling Concrete Behaviors under Blast and Impact Loadings

Journal of Engineering Mechanics ◽

10.1061/(asce)em.1943-7889.0000497 ◽

2013 ◽

Vol 139 (4) ◽

pp. 525-536 ◽

Cited By ~ 11

Author(s):

Youcai Wu ◽

Joseph M. Magallanes ◽

Hyung-Jin Choi ◽

John E. Crawford

Keyword(s):

Finite Element ◽

Finite Element Mesh ◽

Element Mesh ◽

Mesh Free

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Surface reconstruction from FE mesh model

Journal of Computational Design and Engineering ◽

10.1016/j.jcde.2018.05.004 ◽

2018 ◽

Vol 6 (2) ◽

pp. 197-208 ◽

Cited By ~ 1

Author(s):

Jung Min Park ◽

Byung Chai Lee ◽

Soo Won Chae ◽

Ki Youn Kwon

Keyword(s):

Finite Element ◽

Finite Element Mesh ◽

Design Stage ◽

Free Form ◽

Surface Model ◽

Element Analysis ◽

Element Mesh ◽

Design Modification ◽

B Spline ◽

Mesh Model

Abstract In the computer aided engineering process with finite element analysis, a CAD surface model is sometimes needed for various tasks such as remeshing, shape optimization or design modification. Occasionally, engineers who perform an analysis at the product design stage are given only finite element mesh models; corresponding CAD models can be unavailable. This paper presents a method to extract free-form B-spline surfaces and certain feature curves from a surface mesh model. First, using the k-means clustering method, our process segments given meshes into a number of regions according to principal curvature information; then, region operations are performed. Next, each region is converted to an approximately free-form B-spline surface. In the last step, feature curves to create loft or sweep surfaces are calculated by minimizing the distance error. Some practical examples are also presented to demonstrate the effectiveness and usefulness of our method. Highlights We propose a new method of creating CAD surfaces from given finite element mesh model. Feature curves are extracted for creating sweep or loft surfaces. By using the generated surfaces based on the feature curves, the shape modification can be easily performed in the designing process.

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The Influence of Ball Impact Angle on the Brain Deformation in Soccer Heading: A Finite Element Analysis

10.1007/978-981-16-4115-2_25 ◽

2021 ◽

pp. 313-320

Author(s):

Mohd Hasnun Arif Hassan ◽

Mohd Alimin Mohd Anni ◽

Fu Yang Tan ◽

Nasrul Hadi Johari ◽

Mohd Nadzeri Omar

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Impact Angle ◽

Element Analysis ◽

Ball Impact ◽

Brain Deformation ◽

The Brain ◽

Soccer Heading

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Reconstruction of B-rep Solid Models From Finite Element Meshes for Design Automation

19th Design Automation Conference: Volume 2 — Design Optimization; Geometric Modeling and Tolerance Analysis; Mechanism Synthesis and Analysis; Decomposition and Design Optimization ◽

10.1115/detc1993-0375 ◽

1993 ◽

Author(s):

Andrei G. Jablokow ◽

Isaac Abraham

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Design Automation ◽

Boundary Representation ◽

Finite Element Mesh ◽

Solid Model ◽

Element Analysis ◽

Element Mesh ◽

Solid Models ◽

Finite Element Meshes

Abstract This paper presents the integration of Finite Element (FE) techniques with B-rep solid modeling. Algorithms for constructing B-rep solid models from a finite element meshes are presented. The finite element mesh data, which consists of node coordinates and connectivity information, is read in from any standard finite element analysis package (currently SDRC IDEAS and MSC/XL) and then processed to construct a polyhedral non-manifold B-rep solid model of the geometry. Since the finite element mesh of a solid object is essentially a non-manifold object, existing geometric modeling data structures based on two-manifold topologies cannot represent it directly. In this work the non-manifold radial-edge data structure is used for the internal representation of the finite element mesh. The mesh is then processed using non-manifold topology operators to eliminate internal nodes and elements to arrive at the solid model that is a polyhedral boundary representation. The results are useful for design automation through the integration of CAD with finite element analysis, shape optimization, as well as the manufacturing of geometry stored as a finite element mesh.

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Influence of finite element mesh size on the carrying capacity analysis of single-row ball slewing bearing

Advances in Mechanical Engineering ◽

10.1177/16878140211009030 ◽

2021 ◽

Vol 13 (4) ◽

pp. 168781402110090

Author(s):

Peiyu He ◽

Qinrong Qian ◽

Yun Wang ◽

Hong Liu ◽

Erkuo Guo ◽

...

Keyword(s):

Finite Element ◽

Carrying Capacity ◽

Mesh Size ◽

Finite Element Mesh ◽

Fe Model ◽

Element Mesh ◽

Heavy Load ◽

Slewing Bearing ◽

Maximum Contact ◽

Slewing Bearings

Slewing bearings are widely used in industry to provide rotary support and carry heavy load. The load-carrying capacity is one of the most important features of a slewing bearing, and needs to be calculated cautiously. This paper investigates the effect of mesh size on the finite element (FE) analysis of the carrying capacity of slewing bearings. A local finite element contact model of the slewing bearing is firstly established, and verified using Hertz contact theory. The optimal mesh size of finite element model under specified loads is determined by analyzing the maximum contact stress and the contact area. The overall FE model of the slewing bearing is established and strain tests were performed to verify the FE results. The effect of mesh size on the carrying capacity of the slewing bearing is investigated by analyzing the maximum contact load, deformation, and load distribution. This study of finite element mesh size verification provides an important guidance for the accuracy and efficiency of carrying capacity of slewing bearings.

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