A Phase-Velocity Description of Aerodynamic and Electrostatic Transport of Cotton Fibers and Trash

Abstract

The transport of cotton fibers and particulate trash is considered for the particular case of upward flow at low Reynolds numbers such that electrostatic or gravitational sedimentation effects are significant. A two-phase continuum mechanical approach is used. The conventional velocity-holdup description is modified by casting the equation systems into the velocity domain. The theoretical implications of these effects are analyzed, with emphasis on application to the pneumatic and electrostatic conveying of cotton tufts, fibers, trash, and dusts in axisymmetric vertical pipes. Expressions are derived for the overall gravimetric and volumetric penetrations of a dilute solid phase in a pipe of finite length.