All Questions
Tagged with computational-physics boundary-conditions
18
questions
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Free Time Dependent Schrodinger Equation with Inhomogeneous Dirichlet boundary
There exists a FFT-based method to solve the poisson equation in inhomogeneous Dirichlet boundary condition using the sine-transform. For example, Which fourier series is needed to solve a 2D poisson ...
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1
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Who can explain the minimum image convention in molecular dynamic simulations?
How to choose the cutoff radius so that the atoms do not interact with its periodic image? Especially when simulating macromolecules (proteins).
1
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177
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Integrating a wavelike equation with absorbing boundary conditions
I am trying to numerically solve the following equation:
$\frac{\partial^{2} \phi}{\partial t^{2}}-\frac{\partial^{2} \phi}{\partial x^{2}}+V(x) \phi(x, t)=0$ On some domain, with:
$\phi(x, 0) = I(x)$
...
- 111
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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. ...
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242
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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 ...
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1
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110
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Applying weak form
I have two dimensional equation and I want to solve it using Finite Element Methods.
$$ \nabla . (\alpha(x,y)\nabla u(x,y)) + \dfrac{\partial u(x,y)}{\partial x}+\dfrac{\partial u(x,y)}{\partial y}+u(...
3
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2
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241
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Solving a Boundary Value Question $\frac{d^2y}{dx^2}=y\cos(x)+\frac{\sin(x)}{x^2+2}$ using Python
I'm looking to solve this boundary value question using the shooting method!
$$\frac{d^2y}{dx^2}=y\cos(x)+\frac{\sin(x)}{x^2+2}$$ given the initial values:
$$y'(x=-1)=-1\\y'(x=5)=0$$
I'm aware of ...
user35752
1
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0
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How to avoid density getting "deleted" in two way rigid body coupling with LBM CFD?
I've been reading this paper recently, which talks about using Lattice Boltzmann methods and two way coupling. Specifically, it outlines fluid solid coupling, and solid fluid coupling, and how simply ...
- 161
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215
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Non-reflecting boundary conditions for compressible Navier-Stokes equations
I have some questions about the implementation of non-reflecting OUTFLOW boundary condition for Navier Stokes equations.
Following
Poinsot, Lele "Boundary Conditions for Direct Simulations of ...
- 139
1
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1
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1k
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Proper boundary conditions for potential flow around cylinder
I am computing the stationary, incompressible, inviscid and irrotational flow around a circular cylinder using a discretization in general coordinates.
I derived a PDE and proper boundary conditions ...
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2
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195
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Mass conservation in atmospheric continuity equation numerical solution
My phd project is heavily related to numerical modeling of planetary atmospheres. In particular now I am dealing with a particular expression of the continuity equation, involving a thermodynamic flux....
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269
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How can an engineering student become a computational scinece expert in a short time [closed]
How can a student with zero computing or programming language knowledge, few engineering mathematics knowledge, understand computational science especially Finite Element Modelling (FEM) from ...
1
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2
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157
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Definition of inflow boundary in CFD
If $w$ is the vector of conservative variables, $f=f(w)$ the flux function, I think have read somewhere (I can not find it anymore) that the inflow boundary $\Sigma$_ is characterized by:
$\Sigma_{-}...
- 113
1
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614
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Shooting method - Matlab ODE
I'm trying to solve these equations of hypersonic adiabatic flow over a flat plate. I did all the simplifications and got these equations for the stagnation point flow.
$$\left(Cf''\right)' + f f'' = \...
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2
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343
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Implementation of no-slip boundary conditions in lattice Boltzmann method fluid simulation
My faculty advisor recommended that I take a look at the lattice Boltzmann method as an introduction to scientific computing and potentially an undergraduate honors thesis topic. I cooked up a some ...
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