ABSTRACT
By a "porous medium" is meant a solid, or a collection of solid particles, with sufficient open space in or around the particles to enable a fluid to pass through or around them. There are various conceptual ways of describing a porous medium. The "pile of solid particles" concept is useful for either consolidated or unconsolidated media as a basis for analyzing the flow phenomena, since many consolidated media are actually made up of individual particles that are just stuck together. Because the fluid in a porous medium follows a tortuous path through channels of varying size and shape, one method of describing the flow behavior in the pores is to consider the flow path as a "noncircular conduit." Flow in a porous medium in two or three dimensions is important in situations such as the production of crude oil from reservoir formations, for example.
