Steady-State Flow in a Porous Cylinder With Permeable Walls and Restricted or Unrestricted Ends

Even though flow through porous media has received con-siderable attention, flow through a medium bound by permeable boundaries has not been studied in any detail in the past. Media bound by permeable boundaries are however often encountered in practice. Flow of gases through a cigarette where both the tobacco rod and the wrapping paper are porous is of this type [1).1 A closely related system is that of the graphite block in a gas-cooled nuclear reactor where the nuclear fuel is separated from the rapidly circulating coolant by a porous graphite septum with a narrow gap between fuel and septum [2). Related problems having different geometries include seepage from streams bounded by porous banks [3), leakage into some aquifers [4) and the displacement of oil from sandstones by shalewater influx [5). This type of flow presents certain peculiari-ties, such as the lack of simple additivity of effective resistance