For questions regarding the choice and/or appropriateness of conditions necessary to model a particular phenomenon with a partial differential equations.
Questions tagged [boundary-conditions]
415 questions
4
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1 answer
Symmetric boundary condition
I am solving a flow physics problem, in which I encounter a symmetric boundary. So I set the boundary conditions to be $$\frac{\partial u}{\partial r} = \frac{\partial v}{\partial r}=\frac{\partial w}{\partial r}=\frac{\partial T}{\partial r}…
Rhinocerotidae
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2
votes
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How to implement boundary condition in this case?
Let's start off by NUMERICALLY solving a 1-D steady-state heat transport problem using IMPLICIT FDM.
$DT_{xx}=0; ~T(x=0)=T_{BL}; ~T(x=l)=T_{BR}$
where $D$ is diffusion; $T$ is temperature; subscript $ _{x}$ is the gradient with respective to…
Chenming Zhang
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Minimum box size in order for an object in the center to not 'see' duplications of itself under periodic boundary conditions?
I am working on developing a Dissipative Particle Dynamics (DPD) model of a colloid in a bulk fluid. I essentially want to ensure that the perturbations of my meshed colloid are completely uncoupled from the duplicated copies of itself that are…
cwm5412
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2
votes
1 answer
Periodic boundaries - implementation strategies
I managed to implement the Nearest-Neighboor Ising Model with periodic boundary conditions, it was doable. I also made a modified version of it, where the interaction would go further than the nearest neighbors. In this case the implementation of…
WalyKu
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2
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1 answer
Boundary conditions for second order PDE
For a second order PDE, for example heat conduction equation
$\frac{\partial T}{\partial t} = \frac{\alpha}{C_p} \nabla^2 T$, is it possible to determine the steady-state (or even transient) solution with two Dirichlet conditions? I have two…
vkumar
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vote
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Relation between Stress/Strain and normal derivative of displacement
I calculated the stress $\sigma$ and strain $\varepsilon$ for a solid plate with dirichlet boundary conditions $u = g$, where $u$ is the displacement.
With these I want to calculate $\nabla_n u = t$ on the boundary where $\nabla_n$ describes the…
user29088
1
vote
0 answers
Issues with self-consistent Poisson-Schrodinger solver
I'm currently in the process of writing a self-consistent Schrodinger-Poisson solver for a device heterstructure (High Mobility Electron Transistor). The algorithm is based off of this journal(1). I am having a few difficulties however. It seems…
RRR
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What type of boundary condition(s) do I need to define for a process with diffusion of tracer concentration?
I want to simulate the diffusion of initial dye concentration in a small estuary with a 2D depth averaged model. Would a radiation boundary condition for concentration of tracers alone be enough or do I need to define any additional conditions at…
ZZZ
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Boundary Conditions for Continuum Mechanics
If I'm given some sort of shape and there is a displacement given but there are no external forces acting on the body, do I still need to write down the traction free boundary conditions or will there only be displacement boundary conditions?
HokieFan7
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In the method of weighted residual, is it necessary for the basis function to satisfy the boundary conditions?
In the method of weighted residual applied to boundary value problems, is it necessary for the basis function to satisfy all of the boundary conditions? Will it work even if it does not satisfy all of the boundary conditions?
adipro
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