Introduction Chemical engineers know this as a packed or porous bed. Groundwater hydrologists call this a permeameter or flow through porous media. Another difference is that only Darcy's law requires entering the permeability. Permeability is used rather than hydraulic conductivity since permeability is a soil property independent of fluid while hydraulic conductivity is defined for water only. Any liquid or gas can be used with either method so long as the fluid's density and viscosity are known.
Several fluids have properties built into the program.
The calculation was written in Java using double precision. Valid for any porosity and Reynolds number. Porosity can be computed from packing angle from Idelchik's equation above for packing angles between 60 o and 90 o . Instead of K, k is used in calculations since it is independent of fluid type. Upstream of porous bed.