Two-dimensional nonlinear problems of elastic equilibrium of multiply connected bodies

1970 ◽  
Vol 6 (2) ◽  
pp. 157-163 ◽  
Author(s):  
Yu. I. Koifman
1974 ◽  
Vol 96 (1) ◽  
pp. 335-342
Author(s):  
J. R. Fowler ◽  
E. I. Bailey

The two-dimensional dynamics of an oil containment barrier, which was designed to have very low tensile loads due to current and waves, were simulated with a theoretical model. The model was solved on both analog and digital computers, and a lab test program conducted to verify the model. For nonlinear problems such as this, for which “exact” solutions do not exist, the analog computer has many advantages, principally rapid parameter studies and convenient plotting output, plus giving the engineer a real time “feel” for the problem. The problem treated here was especially well-suited to analog simulation. Charts and graphs present maximum force and amplitude data, and experimental verification of the solution was obtained from wave tank studies.


In a previous communication we employed the solution of the equation ∇ 4 ψ = 0 in bipolar co-ordinates defined by α + iβ = log x + i ( y + a )/ x + i ( y - a ) (1) to discuss the problem of the elastic equilibrium of a plate bounded by any two non-concentric circles. There is a well-known analogy between plain elastic stress and two-dimensional steady motion of a viscous fluid, for which the stream-function satisfies ∇ 4 ψ = 0. The boundary conditions are, however, different in the two cases, and the hydrodynamical problem has its own special difficulties.


1902 ◽  
Vol 70 (459-466) ◽  
pp. 491-496

The paper investigates the elastic equilibrium of a long bar of rectangular cross-section in those cases where the problem may be treated as one of two dimensions, namely:— ( a .) When the strain being in the plane of xy , the elastic solid extends indefinitely in the direction of the applied stresses over the bounding planes y = ± b , x = ± a being the same for any two sections parallel to the plane of xy . We then have a strictly two-dimensional strain.


Author(s):  
Tomoo Yokoyama ◽  
Takashi Sakajo

Let us consider incompressible and inviscid flows in two-dimensional domains with multiple obstacles. The instantaneous velocity field becomes a Hamiltonian vector field defined from the stream function, and it is topologically characterized by the streamline pattern that corresponds to the contour plot of the stream function. The present paper provides us with a procedure to construct structurally stable streamline patterns generated by finitely many point vortices in the presence of the uniform flow. Starting from some basic structurally stable streamline patterns in a disc of low genus, i.e. a disc with a small number of holes, we repeat some fundamental operations that append a streamline pattern by increasing one genus to them. Owing to the inductive procedure, one can assign a sequence of operations as a representing word to each structurally stable streamline pattern. We also give the canonical expression for the word representation, which allows us to make a catalogue of all possible structurally stable streamline patterns in a combinatorial manner. As an example, we show all streamline patterns in the discs of genus 1 and 2.


2001 ◽  
Vol 25 (11) ◽  
pp. 717-726 ◽  
Author(s):  
E. M. E. Zayed ◽  
I. H. Abdel-Halim

The spectral functionμˆ(t)=∑j=1∞exp(−itμj1/2), where{μj}j=1∞are the eigenvalues of the two-dimensional negative Laplacian, is studied for small|t|for a variety of domains, where−∞<t<∞andi=−1. The dependencies ofμˆ(t)on the connectivity of a domain and the Robin boundary conditions are analyzed. Particular attention is given to an arbitrary multiply-connected drum inℝ2together with Robin boundary conditions on its boundaries.


1992 ◽  
Vol 36 (01) ◽  
pp. 30-37
Author(s):  
S. J. Liao

Based on continuous mapping, a kind of analytical method for nonlinear problems, namely, the Process Analysis Method, is described and used to solve two-dimensional nonlinear progressive gravity waves. Solutions at the fourth order of approximation are obtained and compared with Stokesian waves. In contrast to the perturbation expansion method, the Process Analysis Method is independent of small or great parameters and therefore can solve nonlinear problems without small or great parameters.


Sign in / Sign up

Export Citation Format

Share Document