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Abstract The main objective of this thesis, which consists of six chapters, is to introduce an analytical and numerical treatment based on polynomial and nonpolynomial spline functions for the solution of some types of fractional partial differential equations. Based on the Von Neumann method, the stability of the proposed methods is studied. The accuracy of the proposed methods is demonstrated by several test problems. We show that the present methods give better accuracy compared with other methods such as collocation, and spline methods. In chapter 1, we introduce some basic lemmas, definitions and concepts which are needed and used throughout to develop this thesis. We also discuss some fractional partial differential equations, which will be dealt with in the next chapters. In chapter 2, we propose a cubic non-polynomial spline based method to obtain numerical solutions for linear time fractional diffusion equation. This chapter is organized as follows: A method depending on the use of the nonpolynomial spline is derived. The truncation error of the method is theoretically analyzed. In addition, the stability analysis is theoretically discussed. Using the Von Neumann method, the proposed method is shown to be conditionally stable. Finally, two numerical examples are included to illustrate the practical implementation of the proposed method. II In chapter 3, a cubic non-polynomial spline based method is proposed to obtain numerical solutions of the time fractional Burgers’ equation. A method depending on the use of the non-polynomial spline is derived in section two. The treatment of non-linear terms is discussed. In section three, the stability analysis is theoretically discussed, using the Von Neumann method, where the method is shown to be conditionally stable. Finally, two numerical examples are presented in section four to illustrate the practical implementation as well as the accuracy of the proposed method. In chapter 4, a novel approach based on quartic non-polynomial spline for solving the time fractional dispersive partial differential equation is proposed. This chapter is organized as follows: A method depending on the use of the non-polynomial spline is analyzed and derived. The truncation error of the method is theoretically analyzed. In addition, the stability analysis is discussed. Using the Von Neumann method, the proposed method is shown to be unconditionally stable. Finally, one numerical example is included to illustrate the practical implementation of the proposed method. The obtained approximate numerical solutions are showed to maintain good accuracy compared with the exact solutions. In chapter 5, a quadratic polynomial spline based method is proposed to obtain numerical solutions of the nonlinear space- fractional Fisher’s equation. Derivation of the numerical method is presented and discussed in section two. In section three the stability analysis is theoretically discussed, using the Von Neumann method, where the method is shown to be conditionally stable. Finally, a numerical example is included to illustrate the practical implementation of the proposed method. The obtained approximate numerical III solutions are in good agreement with the approximate solutions obtained using two other methods. In chapter 6, we propose a quadratic polynomial spline based method to obtain numerical solutions of the linear time and space fractional Diffusion equation. This chapter is organized as follows: A method depending on the use of the polynomial spline is derived. The stability analysis is theoretically discussed, using the Von Neumann method, where the method is shown to be conditionally stable. Finally, numerical examples are presented to illustrate the practical implementation of the proposed method. The obtained numerical results show that the proposed method is applicable and can be used to get a set of approximate solutions for such type of problem. |