Quasilinearization-Collocation Method for the Numerical Solution of Nonlinear Fractional Volterra Integro-Differential Equations With Logarithmic Weakly Singular Kernel

In this paper, we use quasilinearization technique, product integration rule, and collocation method to present a new numerical method to solve nonlinear fractional Volterra integro-differential equations with logarithmic weakly singular kernel. After examining the behavior of the solution of the integro-differential equation, we convert it into a nonlinear Volterra integral equation with a logarithmic weakly singular kernel. We implement the quasilinearization method on the resulting nonlinear equation and derive a sequence of linear integral equations with low-smooth solutions that are convergent to the solution of the nonlinear equation. By utilizing a regularization technique, we enhance the smoothness of the solutions of the linear equations. Then, we apply collocation method along with the product integration rule, to transform the regularized linear equations into a linear algebraic system with a unique solution. We discuss the convergence of the presented method and estimate the error bounds for the proposed numerical approach. Finally, through several numerical examples, we practically test the effectiveness and accuracy of the proposed numerical method, where the obtained numerical results show their agreement with the discussed theoretical results.