A general approach to hyperbolic partial differential equations by homotopy perturbation method

The hyperbolic partial differential equations (PDEs) have a wide range of applications in science and engineering. In this article, the exact solutions of some hyperbolic PDEs are presented by means of He's homotopy perturbation method (HPM). The results reveal that the HPM is very effective and convenient in solving nonlinear problems.     

Application of homotopy perturbation method to multidimensional partial differential equations

In this paper, an application of homotopy perturbation method (HPM) is applied to solve the kindly of multidimensional partial differential equation such as Helmholtz equation. Comparisons are made between the Adomians decomposition method and HPM. The results reveal that the HPM is very effective and simple and gives the exact solution.     

He's homotopy perturbation method for fourth-order parabolic equations

In this paper, He's homotopy perturbation method is applied to fourth-order parabolic partial differential equations with variable coefficients to obtain the analytic solution. The method is tested on six examples, which reveal its effectiveness and simplicity.     

He's homotopy perturbation method for solving the space- and time-fractional telegraph equations

In this study, homotopy perturbation method (HPM) is used to obtain analytic and approximate solutions of the space- and time-fractional telegraph equations. The space- and time-fractional derivatives are considered in the Caputo sense. The analytic solutions are calculated in the form of a series with easily computable terms. Some examples are given. The results reveal that HPM is very effective and convenient.     

A new homotopy perturbation method for system of nonlinear integro-differential equations

In this paper, a new homotopy perturbation method (NHPM) is introduced to obtain exact solutions of system of nonlinear integro-differential equations. Theoretical considerations are discussed. Two examples are given to demonstrate the efficiency of NHPM to the classical HPM and variational iteration methods.     

Solution of the differential algebraic equations via homotopy perturbation method and their engineering applications

Differential algebraic equations (DAEs) appear in many fields of physics and have a wide range of applications in various branches of science and engineering. Finding reliable methods to solve DAEs has been the subject of many investigations in recent years. In this paper, the He's homotopy perturbation method is applied for finding the solution of linear and nonlinear DAEs. First, an index reduction technique is implemented for semi-explicit and Hessenberg DAEs, then the obtained problem can be appropriately solved by the homotopy perturbation method. This technique provides a summation of an infinite series with easily computable terms, which converges to the exact solution of the problem. The scheme is tested for some high-index DAEs and the results demonstrate that the method is very straightforward and can be considered as a powerful mathematical tool.     

A new analytical method for solving systems of Volterra integral equations

In this paper, a new modified homotopy perturbation method (NHPM) is introduced for solving systems of Volterra integral equations of the second kind. Theorems of existence and uniqueness of the solutions to these equations are presented. Comparison of the results of applying the NHPM with those of the homotopy perturbation method and Adomian's decomposition method leads to significant consequences. Several examples, including the system of linear and nonlinear Volterra integral equations, are given to demonstrate the efficiency of the new method.     

He's homotopy perturbation method for nonlinear differential-difference equations

A new scheme, deduced from He's homotopy perturbation method (HPM), is presented for solving nonlinear differential-difference equations (DDEs). A simple but typical example is applied to illustrate the validity and great potential of the generalized HPM in solving nonlinear DDE. The results reveal that the method is very effective and simple.     

The extended homotopy perturbation method for the boundary layer flow due to a stretching sheet with partial slip

A fully analytical solution of the steady, laminar and axisymmetric flow of a Newtonian fluid due to a stretching sheet when there is a partial slip of the fluid past the sheet has been derived using the extended homotopy perturbation method. The solution differs from that obtained by the classical homotopy perturbation method in that it is capable of generating a totally analytical solution up to any desired degree of accuracy and is not limited to the first-order correction terms. For an eight-decimal accuracy, it is sufficient to take 12 terms in the power series in the perturbation parameter, provided that use is made of Shanks’ transformation. Unlike other similar problems involving mass transfer across the sheet and/or the presence of a transverse magnetic field, the solution for the present problem is relatively insensitive to the velocity slip parameter.     

线性模糊微分系统的同伦摄动法

利用模糊结构元方法,将线性模糊微分系统转换成同解的线性确定微分系统。采用同伦摄动法给出线性确定微分系统的近似解,进而给出原模糊微分系统的近似解。给出了具体算例。     

Solution of BVPs for fourth-order integro-differential equations by using homotopy perturbation method

In this study, the homotopy perturbation method proposed by Ji-Huan He is applied to solve both linear and nonlinear boundary value problems for fourth-order integro-differential equations. The analysis is accompanied by numerical examples. The results show that the homotopy perturbation method is of high accuracy, more convenient and efficient for solving integro-differential equations.     

Using an enhanced homotopy perturbation method in fractional differential equations via deforming the linear part

Convergence and stability are main issues when an asymptotical method like the Homotopy Perturbation Method (HPM) has been used to solve differential equations. In this paper, convergence of the solution of fractional differential equations is maintained. Meanwhile, an effective method is suggested to select the linear part in the HPM to keep the inherent stability of fractional equations. Riccati fractional differential equations as a case study are then solved, using the Enhanced Homotopy Perturbation Method (EHPM). Current results are compared with those derived from the established Adams–Bashforth–Moulton method, in order to verify the accuracy of the EHPM. It is shown that there is excellent agreement between the two sets of results. This finding confirms that the EHPM is powerful and efficient tool for solving nonlinear fractional differential equations.     

Application of homotopy perturbation method and homotopy analysis method to fractional vibration equation

In this paper, the approximate analytical solutions of the mathematical model of vibration equation with fractional-order time derivative β (1<β≤2) for very large membranes are obtained with the help of powerful mathematical tools like homotopy perturbation method and homotopy analysis method. Both the methods perform extremely well in terms of efficiency and simplicity. The validity and applicability of the techniques are shown for obtaining approximate numerical solutions for different particular cases which are presented through figures and tables.     

New Rothe-wavelet method for solving telegraph equations

In this article, we present a new competitive scheme to solve one of the most important cases in hyperbolic partial differential equations which is called telegraph equations. This method is based on Rothe's approximation in time discretisation and on the wavelet-Galerkin in the spatial discretisation. For comparison of wavelets, we use sin–cos, Legendre and Daubechies wavelets as basis in projection methods. For showing efficiency of method, a numerical experiment, for which the exact solution is known, is considered.     

A new parallel domain decomposition method for the adaptive finite element solution of elliptic partial differential equations

We present a new domain decomposition algorithm for the parallel finite element solution of elliptic partial differential equations. As with most parallel domain decomposition methods each processor is assigned one or more subdomains and an iteration is devised which allows the processors to solve their own subproblem(s) concurrently. The novel feature of this algorithm however is that each of these subproblems is defined over the entire domain—although the vast majority of the degrees of freedom for each subproblem are associated with a single subdomain (owned by the corresponding processor). This ensures that a global mechanism is contained within each of the subproblems tackled and so no separate coarse grid solve is required in order to achieve rapid convergence of the overall iteration. Furthermore, by following the paradigm introduced in 15 , it is demonstrated that this domain decomposition solver may be coupled easily with a conventional mesh refinement code, thus allowing the accuracy, reliability and efficiency of mesh adaptivity to be utilized in a well load-balanced manner. Finally, numerical evidence is presented which suggests that this technique has significant potential, both in terms of the rapid convergence properties and the efficiency of the parallel implementation. Copyright © 2001 John Wiley & Sons, Ltd.     

Mixed discontinuous Legendre wavelet Galerkin method for solving elliptic partial differential equations

By incorporating the Legendre multiwavelet into the mixed discontinuous Galerkin method, in this paper, we present a novel method for solving second-order elliptic partial differential equations (PDEs), which is known as the mixed discontinuous Legendre multiwavelet Galerkin method, derive an adaptive algorithm for the method and estimate the approximating error of its numerical fluxes. One striking advantage of our method is that the differential operator, boundary conditions and numerical fluxes involved in the elementwise computation can be done with lower time cost. Numerical experiments demonstrate the validity of this method. The proposed method is also applicable to some other kinds of PDEs.     

A reduce package for determining lie symmetries of ordinary and partial differential equations

Title of program: LIE0,LIE1,LIE2,LIE3,LIE4 Catalogue number: AAZB Program obtainable form: CPC Program library, Queen's University in Belfast, N. Ireland (see application form in this issue) Computer: Siemens 7.760 Operating system: BS 2000 Programming language used: LISP High speed storage required: depends on the problem, minimum about 400 000 bytes No. of bits in a word: 32 Number of cards in combined program and test deck: 200     

On the convergence of variational iteration method for nonlinear coupled system of partial differential equations

In this paper, the sufficient conditions that guarantee the convergence of the variational iteration method when applied to solve a coupled system of nonlinear partial differential equations are presented. Especial attention is given to the error bound of the nth term of the resultant sequence. Numerical examples to show the efficiency of the method are presented.     

A complex variable boundary element method for elliptic partial differential equations in a multiple-connected region

A simple boundary element method based on the Cauchy integral formulae is proposed for the numerical solution of a class of boundary value problems involving a system of elliptic partial differential equations in a multiple-connected region of infinite extent. It can be easily and efficiently implemented on the computer.     

Reliable algorithms for solving integro-differential equations with applications

This paper suggests four different methods to solve nonlinear integro-differential equations, namely, He's variational iteration method, Adomian decomposition method, He's homotopy perturbation method and differential transform method. To assess the accuracy of each method, a test example with known exact solution is used. The study outlines significant features of these methods as well as sheds some light on advantages of one method over the other. The results show that these methods are very efficient, convenient and can be adapted to fit a larger class of problems. The comparison reveals that, although the numerical results of these methods are similar, He's homotopy perturbation method is the easiest, the most efficient and convenient. Moreover, we applied modified forms of He's variational iteration method and differential transform method to solve a mathematical model, which describes the accumulated effect of toxins on populations living in a closed system.