All Questions
Tagged with computational-physics finite-element
38
questions
0
votes
1
answer
77
views
In level set fluid structure interaction method why can we rewrite the elastic force in this form while there is no shear force?
when we consider a Immersed Membrane Without Shear, we can define a regularized elastic energy as $$\mathcal{E}(\varphi)=\int_{\Omega} E(|\nabla \varphi|) \frac{1}{\varepsilon} \zeta\left(\frac{\...
- 193
0
votes
1
answer
132
views
finding weak form of nonlinear differential equation for FEM simulation
The following is the well-known nonlinear differential equation for director's distribution at static equilibrium in liquid crystal displays(LCD). I want to obtain weak form of the given differential ...
- 35
1
vote
1
answer
124
views
What FEM solver should be used for matrix-valued FE spaces?
I am pretty new to using FE solvers. I am trying to solve a system of (up to) 9 complex equations. We write these as a matrix equation (here), (with the implied sum over $j$, for each component ...
- 21
1
vote
0
answers
82
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Finding the weak form of a PDE with a tensor argument
I am trying to solve for the order parameter ($A$) in the Ginzburg Landau equations. I had asked on the math SE site but was recommended to ask here.
We are trying to solve the following equation, (...
- 21
1
vote
2
answers
894
views
Dyadic operations, fourth order tensors and Tensor algebra
I am trying to understand the dyadic operation for a while since I am interested in Elasticity problems. I believe an intuitive understanding (rather than assuming) will give me good problem solving ...
3
votes
2
answers
153
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Efficient schemes for solving the extended Saddle point problem
I am interested in knowing some efficient techniques for solving the following extended Saddle point problem.
\begin{align}
\begin{bmatrix}
A & B^T & C^T \\
B & 0 & 0 \\
C & ...
- 964
3
votes
1
answer
329
views
Finite element method for high-frequency electromagnetics
I am writing a project about the Finite element method for use in high-frequency solutions of Maxwell's equations. This could be for use in antenna design and similar.
I have some trouble ...
- 33
1
vote
0
answers
236
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Solving coupled PDEs with self-consistency condition
I am figuring out how to attack a problem (the Usadel equations of superconductivity) in which I need to solve a set of nonlinear PDEs for the fields $\{G_i (r)\}$
$$ U(G_i(r), \nabla G_i(r), \Delta(r)...
- 171
1
vote
2
answers
760
views
How can I implement second order derivatives of shape functions of a 3D elements?
I am developing an Abaqus UEL with 3D 8 nodes brick elements and I need second order derivatives of the shape functions, I have already mapped the first order derivatives from the element coordinates ...
- 11
9
votes
4
answers
698
views
Finite-difference software for solving custom equations
Are there any good, easy to use, software for simulating the evolution of systems of generic differential equations? I know there are custom programs for various specific circumstances (such as ...
- 201
0
votes
0
answers
319
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COMSOL Circularl polarization
I'm having some problems trying to implement circularly polarized light in COMSOL Muliphysics.
For a isotropic homogenous media, I've obtained without problems the TE and TM reflectance curves. ...
0
votes
0
answers
242
views
Applying boundary Conditions on FEM
I have a partial differential equatons as shown below.
$$\dfrac{d}{dx}((1+x)\dfrac{du(x)}{dx})=0$$
With the following boundary conditions.
$$u(0)=0, u(3)=10$$
To solve it using FEM, I multiplied the ...
5
votes
2
answers
2k
views
Difference between MoM and FEM
Method of Moments and Finite Element Methods are two of the most used methods in computational electromagnetics to solve electromagnetic equations.
As it is known, in FEM sparse matrixes are used ...
1
vote
0
answers
220
views
Lattice spring models vs. finite element models
I am a beginning graduate student in the field of continuum mechanics. It is my understanding that most problems in this field are numerically solved via finite element methods (FEM). However, I have ...
- 11
1
vote
1
answer
75
views
How long should the hyperelastic equations be solved before updating the mesh?
How long should the hyperelastic equations be solved before updating the mesh? To be specific, I'm interested in the hyperelastic model with a neo-Hookean solid:
$$
\nabla\cdot\sigma + f = \rho\ddot{...
- 767