Solution of diffusion–dispersion models using a computationally efficient technique of orthogonal collocation on finite elements with cubic Hermite as basis

• The technique of OCFE by taking cubic Hermite as basis function is explained.
• Method has order of convergence two.
• Method is extendable to non linear stiff problems with equal ease.
• Results from mathematical models are linked with industrial parameters.

In this paper, linear and non linear diffusion–dispersion models involving fluid flow through porous cylindrical particles are solved using orthogonal collocation on finite elements with cubic Hermite as basis. The technique involves partitioning of axial domain into equal elements and then orthogonal collocation method with cubic Hermite as basis function is applied within each element. Exit concentration profiles are drawn for Peclet numbers ranging from 0 (perfect mixing) to ∞ (perfect displacement). Proposed technique is computationally efficient, stable and yields accurate solution, even for nonlinear stiff problem. Correlation with industrial parameters is also presented.