Questions tagged [porous-media]
Porous media are solid materials that contain interconnected pores allowing fluids to pass through.
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Calculating Pore Size from Permeability
I am building an experiment where one has a bed of sand on top of a porous plate. The pores allow air to be blown through the plate from the bottom but the pores must be sufficiently fine to not ...
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Not all anisotropic porous media can be associated with a symmetric permeability tensor $K_{ij}$?
My intuition tells me that permeability $K_{ij}$ of Darcy's Law is symmetric, $K_{ij}=K_{ji}$, and I am looking for an answer to show me why this is not the case.
When measuring the permeability of a ...
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Does theory impose a limitation on the size of the sample to be used for measuring permeability?
Theory imposes no limitation on the size of the sample to be used but
it is evident that in order to minimize effects due to local
inhomogeneities in the material such as concretions, small shale
...
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Time derivative term in Navier Stokes equation for fluid in porous media
I was reading the research paper Homogenization of peristaltic flows in piezoelectric porous media and came across the hydrodynamic equation:
$$\mu \nabla^2 v^f -\underline{ \rho_f (\dot{v}^f + w \...
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Diffusion versus dispersion
What is the difference between diffusion and dispersión in porous media?
In my model mathematical,
Advection-Diffusion-Reaction Equation
Or
Advection-Dispersion-reaction Equation ?
Help please
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No slip boundary condition fully developed flow
My question may seem ridiculous but i'm such a mess please help me.
Lets assume at the inlet of a (cylindrical) pipe there is a constant water flow with parabolic velocity profile .
I know that fully ...
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Kirkendall effect: equilibrium vacancy concentration and pair interaction energy
I am reading the following article on Kirkendall effect leading to the Formation of a Hollow Binary Alloy Nanosphere: A Kinetic Monte Carlo Study. I am unable to understand or find in references the ...
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Numerically solving Navier-Stokes-Darcy (Brinkman) equation
I'm trying to learn fluid dynamics in porous media and I need to solve Navier-Stokes-Darcy (Brinkman) equation numerically but I'm not sure how to do that (I was trying to use method of lines for ...
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Permeability determination (estimation) from geometry in undirectional air flow through porous media
So I have to model a porous wind barrier that would stop the majority of dust from entering but also allows air to go in. I have decided to start with a 1D flow assumption with unidirectional porosity....
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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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Ability of some porous solids to tentatively sit on water for a while before sinking
How does a porous solid such as the cereal "Wheatena" manage to tentatively sit on water for a while before sinking? I assume it initially somehow evades capillary action, perhaps through ...
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Leaking water from leaky pots
I have two absolutely identical pots with round bottoms. Each bottom has the same number of absolutely identical holes drilled in it. In the first pot, all the holes are quite far apart, while in the ...
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Groundwater flow with external forcing
I want to solve the diffusion equation in porous media with some external forcing at the origin. The regular diffusion equation-
$$
\frac{\partial h}{\partial t}=D\nabla^2h
$$
But I want to solve for ...
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Which kind of paper has highest absorption speed? [closed]
I am experimenting to analyse the liquid wicking(radial) behaviour of various liquids. I have performed initial studies and experiments on household paper towels but they tend to deform and stick to ...
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What does it mean for resistance, as it appears in Ohm's law, to be an integral, evaluated over the body as a whole?
In literature I read:
The three linear flux laws mentioned are:
As seen, a correspondence exist between the hydraulic conductivity $K$, thermal conductivity $\lambda$, and electrical conductivity $\...
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