All Questions
Tagged with computational-physics fluid-dynamics
81
questions
0
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65
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Exact Riemann Solver for Multi-Component 1D Euler Model
I am concerned looking for an exact Riemann solver for compressible 1D multi-component Euler equations, supplied with the ideal gases equation of state and under the assumptions:
Mechanical ...
- 11
4
votes
2
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169
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Redefining velocity field to make it divergence free on the grid level
I am currently working with convection equation $\frac{\partial C}{\partial t}+u\frac{\partial C}{\partial x}+v\frac{\partial C}{\partial y}=0$. I assume that the velocity field is incompressible i.e. ...
- 173
2
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80
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Preventing an Overflow in Exponential Integrating Factor
The following is the Discrete Spectral Vorticity Evolution PDE for incompressible flow:
$$ \frac{\partial \Omega_{pq}}{\partial t} = \nu \left( \frac{\partial^2 \Omega_{pq}}{\partial x^2} + \frac{\...
- 93
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1
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77
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In level set fluid structure interaction method why can we rewrite the elastic force in this form while there is no shear force?
when we consider a Immersed Membrane Without Shear, we can define a regularized elastic energy as $$\mathcal{E}(\varphi)=\int_{\Omega} E(|\nabla \varphi|) \frac{1}{\varepsilon} \zeta\left(\frac{\...
- 193
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56
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OpenFOAM- write interval changed after restarting simulation
I am running a pimpleFoam simulation on a supercomputer. I have to submit it as a job which has an allocated time. The simulation I was running ran out of this allocated time. So then I restarted it ...
- 101
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1
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157
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Lattice Boltzmann method parallelization
I'm learning about the lattice Boltzmann method (LBM) and how it can be parallelized. On Wikipedia, they say, "The LBM was designed from scratch to run efficiently on massively parallel ...
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63
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What happens at the interface between a solid and a fluid?
I am doing an MPM simulation of water colliding against a solid, I am currently encoding the model for collision forces and I am realising something isn't clicking.
Let us assume the fluid experiences ...
- 273
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41
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Energy potential involvign pressure and viscoscity?
Making a really long explanation short. I am looking for an energy density function for an incompressible isotropic fluid that involves both viscoscity and pressure.
The reason is, there is a way to ...
- 273
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55
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Solving a minimization problem without flattening inputs?
I am reading this paper on improving time steps for solving simulation problems:
https://www.math.ucla.edu/~jteran/papers/GSSJT15.pdf
The authors developed this energy function:
$$E(x) = \frac{1}{2\...
- 273
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135
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Adding stability to MPM simulation?
I am writing a 2D implementation of MLS-MPM, I have fluids working perfetly fine, solids technically work as well, at low time steps.
This is the fluid simulation at a large time step:
https://i....
- 273
1
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0
answers
85
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SPH example codes for solving differential equations
I'm quite new to the smoothed particle hydrodynamics method, so I'm trying to find Matlab or Python code to help me understand it. Specifically, I want to know how to solve the one-dimensional ...
1
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0
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56
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How to calculate the reynolds number for airborne wind energy system?
I am asking for some help on how to calculate the reynolds number for an AWES. I know the formula of Re=rhovl/viscosity. I have selected the air foil as Clark y with chord length 3.72m (which will be ...
- 11
0
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50
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How to specify the value of pressure in a point in solving steady stokes equation numerically?
I try to solve the steady-Stokes equation numerically on , that is
\begin{aligned}
-\nabla \cdot \mathbb{T}(\mathbf{u}, p) & =\mathbf{f} \quad \text { on } \Omega=[0,1]*[-0.25,0], \\
\nabla \cdot \...
- 193
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1
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113
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Aerofoil study using CFD, struggling to find aerofoil coordinates
I’ve been messing around with Ansys and I’m struggling to find the aerofoil coordinates for a NACA 66-012?
I looked on Airfoil tools, but it doesn’t allow you to generate a 6 series aerofoil, only 4 ...
- 1
-1
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1
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154
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The local and average Nusselt number in a square cavity
I am in the process of programming the local & average Nusselt number in a left vertical wall but my Matlab script gives me inappropriate values and it doesn't change with changing of Rayleigh ...
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