This paper represents a system of variable-order (VO) time fractional 2D Burgers equations and expresses a semidiscrete approach by applying the 2D Chelyshkov polynomials (CPs) for solving this system. In this model, the fractional derivative of the Caputo type is considered. To solve this system, we first discretize the VO time fractional derivatives. Next, we obtain a recurrent algorithm by using the weighted finite difference method with parameter . Then, utilizing the 2D CPs, we expand the unknown solution and replace it in the main system. In the sequel, we use the differentiation operational matrices and the collocation method to extract an algebraic system of equations which can be easily solved.The validity of the formulated method is investigated through three numerical examples.
KEYWORDS
2D burgers equation, Chelyshkov polynomials (CPs), variable-order (VO) time fractional derivative
MSC CLASSIFICATION
35R11
INTRODUCTIONThe subject of variable-order (VO) fractional calculus (integration/differentiation of VO fractional order ) is a useful mathematical tool for deeper analysis of dynamical phenomena. 1 In fact, the mathematical systems modelled by this novel concept in science and engineering show more accuracy and sensitivity. 2 We remind that obtaining an analytical solution for the problem that includes VO fractional operator is often very complex and usually impossible. So, using approximate methods are inevitable for solving such problems. The interested reader can find some numerical methods for solving such VO fractional problems in previous works. [3][4][5][6][7] By using the time fractional model of Burgers' equation, many problems in physics can be modelled such as electromagnetic wave, weak shock propagation, flow systems, electromagnetic waves and shock waves in a viscous medium. [8][9][10][11] So, solving different types of this equation is highly demanded. An approximate technique for solving a system of fractional Burgers' equations has been proposed in Korpinar et al. 12 Li et al. 13 suggested a numerical scheme for the time fractional model of Burgers' equation by employing the separation of variables method and Cole-Hopf transformation. The method of differential transformation has been applied in Abazari and Borhanifar 14 for solving some categories of the Burgers equation. In Veereshaa and Prakashab, 15 a numerical method for solving coupled time fractional Burgers' equation has been proposed.The Chelyshkov polynomials (CPs) as a most important sequence of polynomials have many privileges, such as the orthogonality and spectral accuracy. During recent years, the CPs have been extensively employed for solving diverse