Multiphase flow in a roll press nip
نویسندگان
چکیده
A three-phase ensemble-averaged model is developed for the flow of water and air through a deformable porous matrix. The model predicts a separation of the flow into saturated and unsaturated regions. The model is closed by proposing an experimentally-motivated heuristic elastic law which allows large-strain nonlinear behaviour to be treated in a relatively straightforward manner. The equations are applied to flow in the ‘nip’ area of a roll press machine whose function is to squeeze water out of wet paper as part of the manufacturing process. By exploiting the thin-layer limit suggested by the geometry of the nip, the problem is reduced to a nonlinear convection-diffusion equation with one free boundary. A numerical method is proposed for determining the flow and sample simulations are presented.
منابع مشابه
The Dynamics of a Roll Press Nip Albany International
The press section of a paper machine is designed to remove by mechanical means the maximum possible amount of water from a just-formed paper sheet. The paper sheet is carried by a textile fabric conveyer belt through a series of roll nips, which cause water to be transferred from the sheet to the fabric. In the most general case the problem to be considered at each press nip involves transient ...
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