A mathematical model of simultaneous heat and mass transfer was
presented to describe for the first time the effects of the variation in
the characteristic parameters of the membrane during the VMD process on
the permeation flux. The modelling approach was derived by dividing the
module axially into multi-cells and a set of nonlinear simultaneous
equations representing the VMD process were numerically solved via
FSOLVE code. The validation of the presented model was estimated by
simulation with a wide range of 135 diverse published experimental
results related to the influence of various operating conditions, module
properties, and membrane characteristics on the water permeation flux
through the membrane. A good agreement was obtained between the
experimental data and the results of the developed model. The same
change in the membrane characteristics during the MD operation reported
experimentally in the literature was confirmed by the simulation results
of the developed model.