Questions tagged [finite-element-method]
The finite-element-method tag has no usage guidance.
298
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How can I determine the best thicknesses of a circular plate to achieve minimum weight and high strength?
I want to design a circular plate made from iron ductile material, So I want to determine the best thicknesses of the profile (t1,t2,t3,...etc) as shown in the image tyo achieve the best plate weight ...
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What is the difference between maximum principal strain and maximum in-plane principal strain?
For the purpose of answering/explaining this, it does not need to be restricted to strains (i.e., it can be stresses too). I am mainly trying to understand when to use which one (i.e., if I am ...
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FEA meshing of irregular geometry
I work on the simulation of sand particles and usually use tetrahedral free-meshing to represent their complex geometries for finite element analysis. I have recently spent some time looking into ...
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Deformation Due to Material Removal and Residual Stress
Suppose I have a piece of metal (of arbitrary geometry) with some residual stress profile. I then remove a chunk of the metal and the piece of metal deforms (due to the residual stress). For ...
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Checking if a Residual Stress Field Achieves Mechanical Equilibrium
Suppose I told you the Cauchy Stress Tensor at every point inside a chunk of metal. And, yes, I know this means that I would need to tell you about an infinite number of points - let's ignore that ...
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Beam deflection for FEA model validation
I'm trying to validate an FE model that I'm using by comparing to a simplified analytical solution to the problem.
The part I'm analyzing is a lug that is constrained on one end and has a point load ...
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Creating a state-space representation (.m format, Matlab) via Simcenter 3D (NASTRAN) using Component Mode Synthesis Reduction
I'm trying to create a state-space representation of my FE-model using a "Component Mode Synthesis Reduction" (general form of Craig-Brampton reduction). The picture underneath shows (...
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Specific Heat, Pore Fluid In ABAQUS
I want to model a problem that the theory behind is in the "Coupled Pore Fluid Flow and Stress Analysis" context that there is in the ABAQUS online documentation, version 2022. The link to ...
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New to AutoCAD, trying to accomplish a simple task of trying to simulate how much force can a U channel withstand
Sorry if my question or parts of it seem vague or stupid, I'm fairly new to mechanical engineering. I'm part of a team that is building a simulator platform and I am mostly at the helm of the software ...
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What is the meaning of the traction continuity condition in the generalized momentum balance (continuum mechanics)?
In Nonlinear Finite Elements for Continua and Structures by Belytschko and al. it is stated:
As we have already noted, the strong form, or generalized momentum balance, consists of the momentum ...
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Define material from Ogden–Holzapfel two-fiber strain-energy function in Ansys
I'm trying to do a FSI simulation with properties, described in this paper and for the structural properties, the authors use an Ogden–Holzapfel two-fiber strain-energy function to describe the solid ...
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Aligning stresses from one element to another from FEM
I have a Finite Element Model (FEM) and from this model I want to transform the stresses of one element such that they align to another element's axis.
Element A:
Centroid: [7195, 5151, 479]
...
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66
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Finite Element Method for Spherical Objects
I am familiar with the procedure of the FEM for simple planar objects like truss and etc. but my question would be whether it would be possible to use this method to calculate the stiffness or ...
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Deformation in nano timescales for stress > UTS
I am investigating the deformation of high-strength carbon steel past its UTS, subject to extreme pressures of order 1e+19 Pa, but applied in small timescales (100-500 ns). For a material, such as ...
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Deformation Under High Pressure
If a FEA model suggests that a material deforms in a certain way for a max pressure of 1e+11, 1e+13, 1e+15, can it be suggested that the same "direction" of deformation would be true?
I have ...
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Iterative Method through FEM
Due to reasons, I can not fully describe the process explicitly so I will be using substitutes to represent the variables.
Nomenclature:
x - an independent variable
y - another independent variable
Fz ...
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Is there a way to program a buckling analysis of an arbitrary shape, using a standard programming language/libraries (not Abaqus)?
I am trying to develop a program in Python that runs a few different basic analyses for optimization like minimizing compliance and buckling. I want to use machine learning to try to develop a fast (...
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Simulating the Impact of Bicycling on Hip Joint Cartilage
Sorry if this question comes off as obvious. I have more of a biology/clinical research background, and I have almost 0 experience with FEA.
I have 50 sequential data points of the hip joint angles of ...
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Benchmarking Geometrically Exact Beams: Clarification Needed on Material Density?
In an early paper on Simo, I came across an example titled "Cantilever 45-degree bend subject to fixed and follower end load". A force of $600N$ and $300N$ was applied at the end, resulting ...
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Boundary conditions for Clevis fork (linear elasticity)
consider the Clevis fork domain (see here for an image https://www.traceparts.com/it/product/camloc-motion-control-h1-stainless-steel-clevis?CatalogPath=TRACEPARTS%3ATP01001005&Product=10-12112014-...
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Clarification on the location of stress and strain output value in Abaqus
Today, I had a discussion with my teacher about the location of stress and strain output in Abaqus. I believe that Abaqus outputs stress and strain based on Gauss integration points. However, my ...
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Designing a Torsional Rotary Flexure - Finite Element Freeware?
I am interested in designing and building a flexure based telescope tracking accessory. The core of the design would be what I think is called a "rotary flexure" or "Twist-it" or ...
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How can I input the equation below in Abaqus （Operate on XY Data） with certain condition? Where fi=5+5i and frequency range is between 300-950; S=189
Where fi=5+5i and frequency range is between 300-950; S=189.
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Determining the critical load of a fixed beam with non-uniform cross-section?
I am a computer scientist, not a mechanical engineer, so it is absolutely possible that I am missing some basic understanding here.
I have a beam that is fixed in both ends and my goal is to ...
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Boundary condition of vibrating flange in ANSYS mechanical
I have a structure with both sides a having flange. The vibration comes to plant from one of the flanges. The structure has it's own fixed support on its bottom, bearing its weight.
I assumed force is ...
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What are the possible reasons that a finite element simulation would converge successfully at larger element sizes but not at smaller element sizes?
When running a finite element simulation that converges at larger element sizes but not at smaller element sizes, what are the potential sources of the problem? I am wondering in what areas must a ...
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Mode shape directionality in Abaqus finite element analysis
For a coupled aero-structural analysis I'm working on, I have to extract the eigenvectors/mode shapes of my structure, so that I can run aerodynamic calculations on them. I have a parameter (in this ...
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FEA of Rectangular Body Under the Effects of Combined Rotational and Translational Shear
First image is model setup. Clasp is rigidly constrained at top surface. Rectangular beam is affixed to clasp at clasp faces (locally constrained), by way of adhesive pads (second and third images).
...
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Theoretically when a homogeneous isotropic bar is subjected to axial loading, does it fail in shear?
I m referrencing James M Gere, Timoshenko Mechanics of Materials Chapter 2 Page 106. The book talks about effect of uniaxial load on a small element that is inclined in one axis. So my question is if ...
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Comparison between hand calculations of a continuous beam with FEA simulation (Solidworks)
I've seen many videos and books where statically determined beams' hand calculations are checked using FEA. But why is it that FEA results don't match the ones obtained using hand calculations (in ...
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A benchmark to check the validity of a finite element analysis
Is there any well-established benchmark to test the validity of a finite element analysis, i.e. FEA? For example, a 3D model with specific loading and boundary conditions. Along with the expected ...
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Residual Stress Induced By Shot Peening
I'm interested in the residual stress profile induced by shot peening. Most of the papers I have read do some measurement and include a graphic which looks like:
This graphic identifies how the ...
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Possible Modification to Contour Method for Residual Stress Measurement
I've been studying the contour method for measuring residual stress. See https://www.lanl.gov/contour/ if you are not familiar.
In the contour method, a single cut is made all the way through the ...
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Simulation of the direct piezoelectric effect using FEM
I have to simulate the direct piezoelectric effect, i.e. the generation of electrical charge under an applied mechanical strain using FEM with FEniCS. My geometry is a freestanding quadratic prism (a ...
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How can I recover the deformation gradient from the finite element strain result
I have performed a finite element simulation which corresponds to the example in https://de.wikipedia.org/wiki/Deformationsgradient#Beispiel .
The result from the theory in wikipedia is the following (...
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Using Strain Tensors to Recover Stress Tensors
Disclaimer:
I am very new to the field of mechanics, my background is in electrical engineering. I apologize in advance if anything is horribly wrong.
My references are:
"First Course in FEM, 4th ...
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Why do Eigenmodes of a rigid system also diagonalize the Mass and the stiffness matrix seperately?
To set up my question, I will briefly recap the derivation that is usually given for eigenmodes of a system:
If there is no force present, and a body is described by a vector $u$, then the equations ...
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Simulating oscillating loads on Ansys Workbench
I am working on a project to perform fatigue analysis and frequency analysis on a tandem bike that I modeled. How do I simulate the oscillating loads involved in pedalling?
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Hexamesh of a helical coil in ICEM CFD
I am trying to mesh a helical coil segment in ICEM CFD. My approach is to create a 3d block at the start of the geometry, and then extrude it along the center curve:
However, when I do this I end up ...
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Lifting a table using linear rails and linear actuators
I'm trying to design a coffee table for a tightly constrained space that can lift up to become a dining table. I've drawn the CAD for this design, but I'm concerned that the moment arm on the linear-...
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Units of measurement for structural analysis
FEA engine
I'm using CCX finite elements analysis engine along with its pre- and post-processor CGX:
http://www.dhondt.de/index.html
https://github.com/calculix
Example
I'm looking at one example here ...
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Wanting to solve an abaqus step many times with different material properties
I'm going to ask this question, and I am not even sure that what I have in my head is possible.
I have a model with 5 part instances. To understand the effect of material parameter values on part ...
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How does one post process in LS dyna for a seat belt?
Intro: I am looking to use LS Dyna to model a dummy crash.
I have done all the dummy positioning and set up but can not find any tutorials or info on the post process, boundary conditions and running ...
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How to calculate Strain Energy Density from Abaqus hyperelastic simulation?
I am modeling a deformation of a rubber material using Abaqus/Explicit using Ogden hyperelastic model. I can visualize Stress (S) and Displacements (U), but I am interested in plotting the strain ...
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How to add point mass in 3D mass matrix
I have a eigenfrequency simulation $ M * \ddot{\vec{x}} + K * \vec{x} = \vec{0} $
and want to add point masses to certain nodes. The only example I have is a 1D matrix where all of the mass at node 1 ...
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Displacement vectors and linearised angles vectors from local finite element frame to rotated global frame
$s=R\tilde{s}$ is fine, but why $\theta=R\tilde{\theta}$? Namely: why vectors of linearised rotations $\theta_i$ and $\theta_j$ (at nodes $I$ and $j$ respectively) are rotated like they were vector ...
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Abaqus error: Too many attempts for hyper-elastic pneumatic inflation simulation
I encounter the too many attempt error in my hyperelastic silicone rubber soft actuator inflation simulation. This is the original structure:
This is the air pressure load and Boundary constraint ...
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Effect of bracing on a music instrument top - is FEM modal analysis enough to predict this?
I'm currently building a music instrument (string instrument), and I am at the step where one applies certain braces to the soundboard. Since I actually don't know how the bracing will affect the ...
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Conversion of elastic moduli for plane stress case
For isotropic material an elastic modulus, like Young's modulus and in combination with a Poisson ratio can be used to convert to any other elastic modulus, like for example the bulk modulus. Tables ...
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Plate theory vs FEA
I’ve modelled a plate in Abaqus FEA, and I also calculated the Stress and deflection by hand using plate theory-
Why is it that plate theory and simulation deflection and Bon Mises stress values vary ...
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