# Hydraulic Conductivity

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

Hydraulic conductivity, abbreviated as k, is the ease with which a fluid can move through porous spaces or fractures.  Smaller the particles, means smaller the pores (area available for flow), more friction resistance, has lower hydraulic conductivity.  The larger the particles, means larger the pores, less friction resistance, has higher hydraulic conductivity.

## hydraulic conductivity formula

 $$\large{ k = \frac{ Q }{ i \; A_c } }$$

### Where:

 Units English Metric $$\large{ k }$$ = hydraulic conductivity $$\large{\frac{ft}{day}}$$ $$\large{\frac{m}{day}}$$ $$\large{ A_c }$$ = area cross-section $$\large{ft^2}$$ $$\large{m^2}$$ $$\large{ Q }$$ = flow rate $$\large{\frac{ft^3}{sec}}$$ $$\large{\frac{m^3}{s}}$$ $$\large{ i }$$ = hydraulic gradient $$\large{dimensionless}$$

## Related Hydraulic Conductivity formula

 $$\large{ k = \frac{v}{i} }$$ (Darcy velocity)

### Where:

$$\large{ k }$$ = hydraulic conductivity

$$\large{ v }$$ = Darcy velocity or flux

$$\large{ i }$$ = hydraulic gradient