The motion of fiber suspensions in ducts

The paper presents a general study of the rheology of fiber suspensions in liquid flow in ducts, with particular attention paid to the behavior of the coefficient of friction of the suspensions. The behavior of the suspensions is studied as a function of fiber geometry, of flow regime (laminar or turbulent) and of Reynolds number. The effect of turbulent fluctuations in the vicinity of a wall is studied along with the effect of mean flow in wall regions. It is concluded that the effect of the fibers on flow resistance depends on fiber geometry and concentration, while the coefficient of friction of the suspension depends on these same two parameters together with Reynolds number.