Coefficient of permeability determined by measurable parameters

Area of Science:

• Geotechnical Engineering
• Hydrogeology
• Soil Science

Background:

• Coefficient of permeability (hydraulic conductivity) selection often involves significant expert judgment.
• Existing methods can lead to accuracy variations exceeding an order of magnitude.
• A need exists for a more objective and accurate determination of permeability.

Purpose of the Study:

• To develop a method for determining the coefficient of permeability based on measurable physical characteristics of porous media.
• To reduce the reliance on subjective judgment in permeability assessments.
• To provide a more accurate and physically intuitive approach to permeability calculations.

Main Methods:

• Deriving the coefficient of permeability from measurable parameters: fluid density and viscosity, media porosity, average hydraulic radius, and gravitational constant.
• Calculating the hydraulic radius using grain size distribution analysis, assuming spherical particles and incorporating a particle shape factor.
• Utilizing standard test procedures for measuring all variables except the shape factor.

Main Results:

• A procedure is presented to calculate the coefficient of permeability from fundamental, measurable properties.
• The method accounts for fluid properties and porous media characteristics like porosity and pore geometry.
• The calculation of hydraulic radius incorporates grain size distribution and a shape factor.

Conclusions:

• This approach offers a more objective and accurate determination of hydraulic conductivity compared to traditional judgment-based methods.
• The method enhances understanding by visualizing the physical flow process through measurable parameters.
• The derived procedure is applicable to both liquid and gas fluids under laminar flow conditions.