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1.
In this paper, first we survey some recent advances in the study of traveling wave solutions to the Burgers-Korteweg-de Vries equation and some comments are given. Then, we study a Burgers-Korteweg-de Vries-type equation with higher-order nonlinearities. A qualitative analysis to a two-dimensional autonomous system which is equivalent to the Burgers-KdV-type equation is presented, and indicates that under certain conditions, the Burgers-Korteweg-de Vries-type equation has neither nontrivial bell-profile solitary waves, nor periodic waves. Finally, a solitary wave solution is obtained by means of the first-integral method which is based on the ring theory of commutative algebra.  相似文献   

2.
In this work, we have investigated Coriolis effect on oceanic flows in the equatorial region with the help of geophysical Korteweg–de Vries equation (GKdVE). First, Lie symmetries and conservation laws for the GKdVE have been studied. Later, we implement finite element method for numerical simulations. Propagation of nonlinear solitary structures, their interaction and advancement of solitons can be seen in the results so produced. Additionally, Gaussian initial condition and undular bore initial condition are also investigated. Results so obtained have been found in perfect agreement with the available results. Bifurcation analysis of the oceanic traveling wave of the GKdVE is presented depending on traveling wave velocity and Coriolis parameter. It is discerned that velocity of the traveling wave and Coriolis parameter affect significantly on the propagation of the nonlinear waves.  相似文献   

3.
We consider existence of three-dimensional gravity waves traveling along a channel of variable depth. It is well known that the long-wave small-amplitude expansion for such waves results in the stationary Korteweg–de Vries equation, coefficients of which depend on the transverse topography of the channel. This equation has a single-humped solitary wave localized in the direction of the wave propagation. We show, however, that there exists an infinite set of resonant Fourier modes that travel at the same speed as the solitary wave does. This fact suggests that the solitary wave confined in a channel of variable depth is always surrounded by small-amplitude oscillatory disturbances in the far-field profile.  相似文献   

4.
In this work, we study the integrability aspects of the Schamel–Korteweg–de Vries equation that play an important role in studying the effect of electron trapping on the nonlinear interaction of ion‐acoustic waves by including a quasi‐potential. Lie symmetry analysis together with the simplest equation method and Kudryashov method is used to obtain exact traveling wave solutions for this equation. In addition, conservation laws are constructed using two different techniques, namely, the multiplier method and the new conservation theorem. Using the conservation laws and symmetries of the underlying equation, double reduction and exact solution were also constructed. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

5.
By means of the two distinct methods, the Exp-function method and the extended (G′/G)-expansion method, we successfully performed an analytic study on the (2 + 1)-dimensional Schwarzian Korteweg-de Vries equation. We exhibited its further closed form traveling wave solutions which reduce to solitary and periodic waves. New rational solutions are also revealed.  相似文献   

6.
In this paper, a modified Korteweg–de Vries (mKdV) equation and Korteweg–de Vries (KdV) equation at critical ion density are derived for dusty plasmas consisting of hot dust fluid, nonisothermal ions and two-temperature electrons. The charge fluctuation dynamics of the dust grains has also been considered. It has been shown that the presence of a second component of electrons modifies the nature of dust acoustic (DA) solitary structures. The effects of two-temperature electrons, obliqueness and external magnetic field on the properties of DA solitary waves are discussed. Numerical investigations show that there exists only rarefactive solitary waves.  相似文献   

7.
A universal model for the interaction of long nonlinear waves and packets of short waves with long linear carrier waves is given by a system in which an equation of Korteweg–de Vries (KdV) type is coupled to an equation of nonlinear Schrödinger (NLS) type. The system has solutions of steady form in which one component is like a solitary-wave solution of the KdV equation and the other component is like a ground-state solution of the NLS equation. We study the stability of solitary-wave solutions to an equation of short and long waves by using variational methods based on the use of energy–momentum functionals and the techniques of convexity type. We use the concentration compactness method to prove the existence of solitary waves. We prove that the stability of solitary waves is determined by the convexity or concavity of a function of the wave speed.  相似文献   

8.
The viscosity of the medium is taken into consideration in deriving an evolution equation describing the propagation of non-linear centrifugal waves along the free surface of a translational-rotational liquid flow. The result is the Burgers-Korteweg-de Vries (BKdV) equation, for which a steady solution is described in the form of a shock wave with soliton oscillators near the front. Estimates are presented for the effect of viscosity on the wave-front structure and the conditions of formation previously predicted by the author /1/ for centrifugal solitons, which play an important role in various atmosphere processes**.  相似文献   

9.
Exact solutions of KdV equation with time-dependent coefficients   总被引:1,自引:0,他引:1  
In this paper, we study the Korteweg-de Vries (KdV) equation having time dependent coefficients from the Lie symmetry point of view. We obtain Lie point symmetries admitted by the equation for various forms for the time-dependent coefficients. We use the symmetries to construct the group-invariant solutions for each of the cases of the arbitrary coefficients. Subsequently, the 1-soliton solution is obtained by the aid of solitary wave ansatz method. It is observed that the soliton solution will exist provided that these time-dependent coefficients are all Riemann integrable.  相似文献   

10.
Taking the Korteweg-de Vries equation as an example of a soliton system, a connection between conservation laws and infinitesimal transformations (symmetries) is investigated. It is shown that there exist an infinite number of form-invariant infinitesimal transformations. A one-to-one correspondence between conservation laws and infinitesimal transformations is established explicitly. Then it is concluded that the Korteweg-de Vries equation has an infinite number of conservation laws, each of which corresponds to the symmetry of the system. Two methods of weaving an infinitesimal transformation into a finite one are presented; one of them is the extension of the Lie transformation to the nonlinear case, and the other is a transformation reducible to the Backlund transformation. Furthermore, it is found that Hamiltonian formalism naturally leads to the quantization of the wave field. During the discussions, a number of conjectures and theorems which have been proposed in earlier works are confirmed by using the infinitesimal transformation extensively.  相似文献   

11.
In this article, we consider the problem formulation of dust plasmas with positively charge, cold dust fluid with negatively charge, thermal electrons, ionized electrons, and immovable background neutral particles. We obtain the dust‐ion‐acoustic solitary waves (DIASWs) under nonmagnetized collision dusty plasma. By using the reductive perturbation technique, the nonlinear damped Korteweg‐de Vries (D‐KdV) equation is formulated. We found the solutions for nonlinear D‐KdV equation. The constructed solutions represent as bright solitons, dark solitons, kink wave and antikinks wave solitons, and periodic traveling waves. The physical interpretation of constructed solutions is represented by two‐ and three‐dimensional graphically models to understand the physical aspects of various behavior for DIASWs. These investigation prove that proposed techniques are more helpful, fruitful, powerful, and efficient to study analytically the other nonlinear nonlinear partial differential equations (PDEs) that arise in engineering, plasma physics, mathematical physics, and many other branches of applied sciences.  相似文献   

12.
A generalization of the Korteweg-de Vries equation incorporating an energy input-output balance, hence a dissipation-modified KdV equation is considered. The equation is relevant to describe, for instance, nonlinear Marangoni-Bénard oscillatory instability in a liquid layer heated from above. Cnoidal waves and solitary waves of this equation are obtained both asymptotically and numerically.  相似文献   

13.
We consider the solitary wave solutions of a Korteweg–de Vries equation, where the coefficients in the equation vary with time over a certain region. When these coefficients vary rapidly compared with the solitary wave, then it is well known that the solitary wave may fission into two or more solitary waves. On the other hand, when these coefficients vary slowly, the solitary wave deforms adiabatically with the production of a trailing shelf. In this paper we re-examine this latter case, and show that the trailing shelf, on a very long time-scale, can lead to the generation of small secondary solitary waves. This result thus provides a connection between the adiabatic deformation regime and the fission regime.  相似文献   

14.
KdV方程的第二次导出   总被引:2,自引:1,他引:1  
考察R ay le igh1876年关于孤立波的论文及其影响.R ay le igh独立得到了与K dV方程等价的孤立波方程及其孤立波解,建立了比较合理的孤立波近似理论;他的这一工作对于人们认识孤立波的存在性产生积极影响,并对K ortew eg和de V ries1895年的论文有重要影响.  相似文献   

15.
The large‐amplitude internal waves commonly observed in the coastal ocean often take the form of unsteady undular bores. Hence, here, we examine the long‐time combined effect of variable topography and background rotation on the propagation of internal undular bores, using the framework of a variable‐coefficient Ostrovsky equation. Because the leading waves in an internal undular bore are close to solitary waves, we first examine the evolution of a single solitary wave. Then, we consider an internal undular bore, for which two methods of generation are used. One method is the matured undular bore developed from an initial shock box in the Korteweg–de Vries equation, that is the Ostrovsky equation with the rotational term omitted, and the other method is a modulated cnoidal wave solution of the same Korteweg–de Vries equation. It transpires that in the long‐time model simulations, the rotational effect disintegrates the nonlinear waves into inertia‐gravity waves, and then there emerge complicated interactions between these inertia‐gravity waves and the modulated periodic waves of the undular bore, especially at the rear part of the undular bore. However, near the front of the undular bore, nonlinear effects further modulate these waves, with the eventual emergence of nonlinear envelope wave packets.  相似文献   

16.
This paper deals with the existence of solitary waves for Korteweg-de Vries equation with time delay. Based upon the inertial manifold theory and differential manifold geometric theory, the existence of solitary wave solution is proved when the delay is small enough. Up to now, studies on solitary wave for such delay differential equation are not available, so the results of this paper are new.  相似文献   

17.
Solitary and Periodic Solutions of Nonlinear Nonintegrable Equations   总被引:2,自引:0,他引:2  
The singular manifold method and partial fraction decomposition allow one to find some special solutions of nonintegrable partial differential equations (PDE) in the form of solitary waves, traveling wave fronts, and periodic pulse trains. The truncated Painlevé expansion is used to reduce a nonlinear PDE to a multilinear form. Some special solutions of the latter equation represent solitary waves and traveling wave fronts of the original PDE. The partial fraction decomposition is used to obtain a periodic wave train solution as an infinite superposition of the "corrected" solitary waves.  相似文献   

18.
An attempt has been made to obtain exact analytical traveling wave solution or simple wave solution of higher-order Korteweg–de Vries (KdV) equation by using tanh-method or hyperbolic method. The higher-order equation can be derived for magnetized plasmas by using the reductive perturbation technique. It is found that the exact solitary wave solution of higher-order KdV equation is obtained by tanh-method. Using this method, different kinds of nonlinear wave equations can be evaluated. The higher-order nonlinearity and higher-order dispersive effect can be observed from the solutions of the equations. The method is applicable for other nonlinear wave equations.  相似文献   

19.
20.
The linear dispersion relation and a modified variable coefficients Korteweg–de Vries (MKdV) equation governing the three-dimensional dust acoustic solitary waves are obtained in inhomogeneous dusty plasmas comprised of negatively charged dust grains of equal radii, Boltzmann distributed electrons and nonthermally distributed ions. The numerical results show that the inhomogeneity, the nonthermal ions, the external magnetic field and the collision have strong influence on the frequency and the nonlinear properties of dust acoustic solitary waves and both dust acoustic solitary holes (soliton with a density dip) and positive solitons (soliton with a density hump) are excited.  相似文献   

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