Operational matrix method to solve nonlinear reaction-advection-diffusion equation in fractional order system

In the present paper, a numerical scheme is discussed to solve one-dimensional nonlinear diffusion equation of fractional order in which collocation is performed using the Lucas operational matrix. Since the spectral collocation method is used in the proposed method, therefore the residual, initial and boundary conditions of the presented problem are collocated at fixed collocation points. The result is a system of nonlinear equations that can be solved by using Newton’s method. Through error analysis and application to some existing problems, the accuracy of the method is confirmed. The obtained results are presented in tabular forms, which clearly show the higher accuracy of the proposed method. The variations of the solute profile of the proposed model are shown graphically due to the presence or absence of advection and reaction terms for different particular cases.