A novel nonequilibrium method for rigorous simulation of multicomponent
separation columns
Abstract
Nonequilibrium model is a significant improvement in multicomponent
separation process simulation, but more equations are involved and the
solution of the model equations, which relies on an adequate initial
point for convergence of the Newton method, is difficult. In this work,
based on the concept of pseudo-transient continuation approach, we
proposed a new pseudo-transient (PT) nonequilibrium method. The proposed
method decouples the strongly coupled model equations by introducing
dynamic equations for material and energy conservation, as well as
transition equations. Thus, the steady-state solution of the
nonequilibrium model can be obtained through a robust and fast
integration process, and the initial point issue in Newton method can be
effectively avoided. Two simulation cases were used to demonstrate the
advantages and applicability of the proposed PT nonequilibrium method.