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MODELLING OF DISPLACEMENT WASHING OF PULP FIBERS USING THE HERMITE COLLOCATION METHOD

Abstract

A non-linear mathematical model for displacement washing of pulp fibers with suitable boundary conditions is presented. Model equations are divided into two phases: particle phase and external fluid phase. The Hermite collocation method (HCM) is employed to solve the non-linear model equations. The validity and efficiency of the proposed model is demonstrated by comparing the numerical results with the experimental ones. Stability of the proposed method is checked by evaluating L2 and L? norms at different time intervals. Industrial parameters such as displacement ratio and wash yield have been calculated to check the validity of the model. Numerical values obtained from the model equations are presented in terms of 2D graphs.

Keywords
Cubic Hermite polynomials; Peclet number; Biot number; Wash yield; Displacement ratio; Bed porosity

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