Coupled Mathieu Equations: γ-Hamiltonian and μ-Symplectic

Author(s):  
Miguel Ramírez Barrios ◽  
Joaquín Collado ◽  
Fadi Dohnal
Keyword(s):  

1985 ◽  
Vol 55 (6) ◽  
pp. 463-473 ◽  
Author(s):  
J. Hansen


1976 ◽  
Vol 34 (3) ◽  
pp. 301-304 ◽  
Author(s):  
E. Infeld


2001 ◽  
Vol 64 (5) ◽  
Author(s):  
E. Papp ◽  
C. Micu
Keyword(s):  


2020 ◽  
Vol 25 (3) ◽  
pp. 117-132
Author(s):  
E. Strelnikova ◽  
D. Kriutchenko ◽  
V. Gnitko ◽  
A. Tonkonozhenko

AbstractThe paper is devoted to issues of estimating free surface elevations in rigid cylindrical fluid-filled tanks under external loadings. The possibility of baffles installation is provided. The liquid vibrations caused by lateral and longitudinal harmonic loadings are under consideration. Free, forced and parametrical vibrations are examined. Modes of the free liquid vibrations are considered as basic functions for the analysis of forced and parametric vibrations. The modes of the free liquid vibrations in baffled and un-baffled cylindrical tanks are received by using single-domain and multi-domain boundary element methods. Effects of baffle installation are studied. The problems of forced vibrations are reduced to solving the systems of second order ordinary differential equations. For parametric vibrations the system of Mathieu equations is obtained. The numerical simulation of free surface elevations at different loadings and baffle configurations is accomplished. Beat phenomena effects are considered under lateral harmonic excitations. The phenomenon of parametric resonance is examined under longitudinal harmonic excitations.



Author(s):  
Michael D. Stubna ◽  
Richard H. Rand

Abstract We investigate the dynamics of the parametrically-excited P.D.E.(1)∂2u∂t2-c2(∂2u∂x2+∂2u∂y2)+εβ∂u∂t+(∂+εγcos⁡t)u=εαu3 with Neumann boundary conditions on a rectangular region:∂u∂x=0forx=0,π and ∂u∂y=0fory=0,πμ where 0 < μ ≤ 1. Our approach involves expanding u(x, y, t) in a 3-term Fourier series truncation:(2)u=f0(t)+f1(t)cos⁡x+f2(t)cos⁡μy By substituting (2) into (1) we obtain a system of 3 coupled nonlinear Mathieu equations which we analyze using averaging in the neighborhood of 2 : 1 resonance. By varying the parameters c and δ we obtain bifurcation curves which divide the cδ-plane into more than forty regions, each containing a distinct slow flow. Individual regions are found to differ from one another with respect to such features as the number and character of slow flow equilibria, and the presence or absence of a limit cycle. When interpreted in the original variable u, these regions account for a variety of patterns which may be classified as stationary, traveling or rotating. This type of behavior is comparable to various experimental observations made by other investigators on vertically driven fluids or sand.



2019 ◽  
Vol 96 (1) ◽  
pp. 737-750 ◽  
Author(s):  
Subhadip Biswas ◽  
Jayanta K. Bhattacharjee


2017 ◽  
Vol 140 (1) ◽  
Author(s):  
April Bryan

This research presents a study of the free vibration of thin, shallow elliptical shells. The equations of motion for the elliptical shell, which are developed from Love's equations, are coupled and nonlinear. In this research, a new approach is introduced to uncouple the transverse motion of the shallow elliptical shell from the surface coordinates. Through the substitution of the strain-compatibility equation into the differential equations of motion in terms of strain, an explicit relationship between the curvilinear surface strains and transverse strain is determined. This latter relationship is then utilized to uncouple the spatial differential equation for transverse motion from that of the surface coordinates. The approach introduced provides a more explicit relationship between the surface and transverse coordinates than could be obtained through use of the Airy stress function. Angular and radial Mathieu equations are used to obtain solutions to the spatial differential equation of motion. Since the recursive relationships that are derived from the Mathieu equations lead to an infinite number of roots, not all of which are physically meaningful, the solution to the eigenvalue problem is used to determine the mode shapes and eigenfrequencies of the shallow elliptical shell. The results of examples demonstrate that the eigenfrequencies of the thin shallow elliptical shell are directly proportional to the curvature of the shell and inversely proportional to the shell's eccentricity.



PAMM ◽  
2011 ◽  
Vol 11 (1) ◽  
pp. 319-320
Author(s):  
Stefan Hubinger ◽  
Hubert Gattringer ◽  
Hartmut Bremer ◽  
Karl Mayrhofer


1977 ◽  
Vol 4 (1) ◽  
pp. 1-4
Author(s):  
H. Schmieg ◽  
P. Vielsack


Sign in / Sign up

Export Citation Format

Share Document