Mass transport due to oscillatory flow through a prestressed viscoelastic tube with a retentive and absorptive wall

Abstract: An asymptotic analysis is presented for the mass transport of a solute due to volume-cycled oscillatory flow in a prestressed and viscoelastic tube with a reactive wall layer (wall retention and absorption). Based on the homogenization technique, the convection–diffusion transport equation is derived for the developed time-mean concentration, containing the effective transport coefficients of advection and dispersion as functions of oscillation frequency, initial stresses, viscoelasticity of the wall, and the two wall reactions. The present model as applied to gas transport in pulmonary airways under high-frequency ventilation is examined in detail, through comparison with a model in the literature. The dispersion coefficient is independent of the wall properties if the tube is tethered. The gas transport rate is found to be enhanced monotonically when either the reversible phase partitioning or its exchange rate increases. [Copyright &y& Elsevier]