Mathematical Problems in Engineering

Volume 2017, Article ID 6328438, 14 pages

https://doi.org/10.1155/2017/6328438

## A Table Lookup Method for Exact Analytical Solutions of Nonlinear Fractional Partial Differential Equations

^{1}College of Atmospheric Science, Nanjing University of Information Science & Technology, Nanjing 210044, China^{2}School of Physics and Electronic Engineering, Anqing Normal University, Anqing 246133, China^{3}School of Electronic & Information Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China

Correspondence should be addressed to Ji Juan-Juan; moc.621@1270jjj

Received 11 August 2016; Accepted 3 November 2016; Published 3 January 2017

Academic Editor: Hang Xu

Copyright © 2017 Ji Juan-Juan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

#### Abstract

A table lookup method for solving nonlinear fractional partial differential equations (fPDEs) is proposed in this paper. Looking up the corresponding tables, we can quickly obtain the exact analytical solutions of fPDEs by using this method. To illustrate the validity of the method, we apply it to construct the exact analytical solutions of four nonlinear fPDEs, namely, the time fractional simplified MCH equation, the space-time fractional combined KdV-mKdV equation, the -dimensional time fractional Zoomeron equation, and the space-time fractional ZKBBM equation. As a result, many new types of exact analytical solutions are obtained including triangular periodic solution, hyperbolic function solution, singular solution, multiple solitary wave solution, and Jacobi elliptic function solution.

#### 1. Introduction

Fractional partial differential equations (fPDEs) are the generalized form of the integer order differential equations. fPDEs can more accurately describe the complex physical phenomena occurring in fluid dynamics, high-energy physics, plasma physics, elastic media, optical fibers, chemical kinematics, chemical physics, acoustic waves, biomathematics, and many other areas [1, 2]. In recent years, many researchers have shown great interest in the search for exact solutions to nonlinear fPDEs. At present, several methods for finding the exact solutions of fPDEs have been presented, for example, the Adomian decomposition method [3–6], variational iteration method [7–9], homotopy perturbation method [10–13], homotopy analysis method [14, 15], differential transform method [16], spectral methods [17, 18], discontinuous Galerkin method [19], Kansa method [20], fractional subequation method [21], generalized fractional subequation method [22], fractional projective Riccati expansion method [23], exp-function method [24, 25], -expansion method [26–28], functional variable method [29, 30], and first integral method [31, 32].

However, the above methods either are relatively complicated or have large computational cost. We propose a table lookup method in this paper. This method is straightforward and has small computational cost. We apply it to solve nonlinear fractional order partial differential equations with using the fractional complex transform and the modified Riemann-Liouville derivative defined by Jumarie [33]. Jumarie’s modified Riemann-Liouville derivative of order is defined by the following expression [34]:where denotes a continuous function and is the Gamma function.

Moreover, the modified Riemann-Liouville derivative has various useful properties, including the following:

The rest of this paper is organized as follows. In Section 2, the basic ideas and main steps of the table lookup method are given. In Section 3, the exact analytical solutions of the time fractional simplified MCH equation, the space-time combined KdV-mKdV equation, the -dimensional time fractional Zoomeron equation, and the space-time fractional ZKBBM equation are constructed using the proposed method. In Section 4, some conclusions are obtained.

#### 2. Basic Idea of the Table Lookup Method

In this section, we outline the main steps of the table lookup method for solving nonlinear fPDEs. Let us consider a fractional order partial differential equation in the following form: where , , and denote modified Riemann-Liouville derivatives of , represents a polynomial in and its various partial derivatives, and , , and are variables. In the following, we give the main steps of our proposed method.

*Step 1. *First, we use the fractional complex transformation as follows: where is a nonzero constant. Thus, (6) can be transformed into the following nonlinear ordinary differential equation (ODE) of integer order with respect to in sense of the properties of Jumarie’s modified Riemann-Liouville derivative given in (2)–(5):where is a polynomial in and its various derivatives and .

*Step 2. *Integrating (8) once or several times with respect to , setting the integration constant to zero if possible, multiplying both sides of the equation by , and then integrating once again, we obtain different types of the auxiliary equation , where () are constant coefficients that can be determined in this step.

*Step 3. *According to the equation type obtained in Step 2, we create the tables of solutions to the corresponding type of auxiliary equation.

*Step 4. *Looking up the tables and determining the corresponding coefficients and existence conditions of the exact solutions, we successfully obtain the exact analytical solutions to (6).

#### 3. Applications of the Proposed Method

In this section, we apply the table lookup method to construct exact analytical solutions of four nonlinear fPDEs, namely, the time fractional simplified MCH equation, the space-time combined KdV-MKdV equation, the -dimensional time fractional Zoomeron equation, and the space-time fractional ZKBBM equation, which are very important nonlinear fPDEs in mathematical physics and have received much attention from researchers.

##### 3.1. The Time Fractional Simplified Modified Camassa-Holm (MCH) Equation

We now consider the following time fractional simplified modified Camassa-Holm (MCH) equation:where , , and . Equation (9) is a variation of the following equation:

Using the fractional complex transformation , with (9), we can obtain the following nonlinear ODE:

Integrating (11) once with respect to and setting the integral constant to zero, we obtain

Multiplying (12) by and then integrating once again, we obtain where , , and is an integration constant.

According to the solutions of the auxiliary equation presented in [35], the exact solutions of (14) are listed in Table 1: