What is the relation between permeability and porosity?

What is the relation between permeability and porosity?

More specifically, porosity of a rock is a measure of its ability to hold a fluid. Mathematically, it is the open space in a rock divided by the total rock volume (solid and space). Permeability is a measure of the ease of flow of a fluid through a porous solid.

How does porosity affect resistivity?

The resistivity of rocks has a tendency to decrease with increasing porosity. The resistivity of the rocks increases with the increase in the pore fluid resistivity, regardless of the rock types.

What is the resistivity formula?

Resistivity, commonly symbolized by the Greek letter rho, ρ, is quantitatively equal to the resistance R of a specimen such as a wire, multiplied by its cross-sectional area A, and divided by its length l; ρ = RA/l. The unit of resistance is the ohm.

How does permeability affect resistivity?

Permeability increases more rapidly and by a greater amount than resistivity, and therefore the percolation threshold in permeability can also be defined with respect to the resistivity (Kirkby et al. 2016).

What is magnetic permeability formula?

Magnetic permeability is represented as μ (it is pronounced as mu) and can be expressed as μ = B/H, where, B is the magnetic flux density which is a measure of the actual magnetic field within a material and is considered as a concentration of magnetic field lines or magnetic flux per unit cross-sectional area.

What is the relationship between permeability and viscosity of water?

What is the relationship between permeability and viscosity of water? It is found that permeability is directly proportional to the unit weight of water and inversely proportional to its viscosity.

Does porosity increase resistivity?

Open porosity has a greater effect on resistivity than closed porosity. An increase of open porosity by 40% leads to a resistivity increase by 250% while the same increase in closed porosity gives rise to a resistivity increase of only 25%. The influence of true density on electrical resistivity is not significant.

How do you calculate water resistivity?

The total resistivity of water or any other material is measured with a simple formula and equation, which reads ρ= E over J. ρ symbol refers to the overall resistivity of the water in ohm meters.

On which factor does resistivity depend?

The resistivity of a material depends on its nature and the temperature of the conductor, but not on its shape and size. The SI unit of electrical resistivity is the ohm-meter. Hence resistivity is dependent on the temperature.

How do you solve resistance and resistivity?

The resistance of a cylindrical segment of a conductor is equal to the resistivity of the material times the length divided by the area: R≡VI=ρLA. The unit of resistance is the ohm, Ω. For a given voltage, the higher the resistance, the lower the current.

How do you calculate formation resistivity factor?

The formation resistivity factor (Fr) is defined as the ratio of the resistivity of the rock saturated with brine (Ro) to the resistivity of the brine (Rw)….1.2. 9 Formation Resistivity Factor.

Source Relation Notes
Archie [42] FR = ϕ− m For consolidated sands, m = 1.8 to 2.5. For unconsolidated sands, m = 1.3

Which of the following relation is correct for permeability?

The correct relation between magnetic susceptibility and relative permeability is- 1 x = Ur-1 2 x = 4r + 1 3 x = u + 1 4 x = u – 1.

Can two porous systems have the same porosity but different permeability?

For instance, two porous systems can have the same porosities but different permeabilities. One of the most widely accepted and simplest model for the permeability-porosity relationship is the Kozeny-Carman (KC) model [ Kozeny, 1927; Carman, 1937] which provides a link between media properties and flow resistance in pore channels.

How do you derive the permeability-porosity equation for a fractal model?

The classical Kozeny-Carman approach and a fractal pore-space geometry assumption are used to derive a new permeability-porosity equation. The equation contains only two fitting parameters: a Kozeny coefficient and a fractal exponent.

Are porosity-electrical resistivity relationships applicable for hardened cementitious systems?

The applicability of porosity-electrical resistivity relationships for hardened cementitious systems is addressed.

What is permeability of porous media?

[4] Permeability of porous media is usually expressed as function of some physical properties of the interconnected pore system such as porosity and tortuosity.