Showing papers in "Journal of Sound and Vibration in 1973"

TL;DR: In this article, the free vibration of rectangular plates is analyzed using the Ritz method with 36 terms containing the products of beam functions, including clamped, simply-supported, and free edge conditions.

TL;DR: It is shown that typical road surfaces may be considered as realizations of homogeneous and isotropic two-dimensional Gaussian random processes, and a single direct spectral density function provides a road surface description which is sufficient for multi-track vehicle response analysis.

TL;DR: In this paper, a general theory of harmonic wave propagation in one-dimensional periodic systems with multiple coupling between adjacent periodic elements is presented, where the motion of each element is expressed in terms of a finite number of displacement coordinates.

TL;DR: In this article, a refined laminated plate theory is developed which is applicable to fiber reinforced composite materials under impact loading and includes the first symmetric thickness shear and thickness stretch motions.

TL;DR: In this article, a study of the behavior of the acoustic impedance of a range of perforates at medium and high incident sound pressure levels was carried out, which included a detailed experimental programme together with a theoretical analysis of the problem.

TL;DR: In this article, a sufficiently accurate analysis for statics and dynamics of composite laminates is presented, where the displacements are assumed piecewise linear across the thickness and the effects of transverse shear deformations and rotary inertia are included.

TL;DR: In this paper, a discussion of various mathematical models which have been proposed to represent the damping behavior of solid materials, with emphasis on their usefulness in structural dynamic analyses is presented, along with derivations of interrelationships which exist among them.

TL;DR: In this paper, a theoretical analysis of the inviscid, perturbed or acoustic field at a particular frequency, in an infinite, two-dimensional duct of constant cross-section in which the fluid properties, other than the mean axial velocity, are constant; one duct wall has a uniform, locally reacting, frequency dependent wall impedance, the other wall is rigid.

TL;DR: In this paper, a mathematical model that enables one to predict the vortex-excited resonant response of bluff cylinders is introduced, where a modified Van der Pol equation is employed as the governing equation for the fluctuating lift on the cylinder and is coupled to the equation for oscillatory motion of the body.

TL;DR: In this article, the authors used Lighthill's acoustic analogy to study the sound radiated from free flows without dissipation, in the limit as the sound speed tends to infinity.

TL;DR: In this paper, a new finite element with three degrees of freedom at each of two nodes is presented and the rates of convergence of a number of the elements are compared by calculating the natural frequencies of two cantilever beams.

TL;DR: In this paper, a general theory for the dynamics of cylindrical beams immersed in purely axial, uniform and steady flow is presented, where cylinders may be either isolated or be part of a cluster of identical cylinders.

TL;DR: In this article, the effects of structural joints on the damping of built-up structures are discussed, and the energy dissipation mechanisms associated with squeezing, rocking, and shearing motions are discussed for simple joints that are dry, lubricated, or provided with viscoelastic inserts.

TL;DR: In this article, it is shown that for a circular duct an array consisting of two separated rings of sources, each composed of three point sources, can be made to generate a plane wave output in one direction only, and that such an array of sources will not generate any propagating transverse modes for frequencies below ωu(M) = 2·1 ωc(M).

TL;DR: In this article, a convenient dynamic stiffness matrix method for converging with certainty upon any particular natural frequency of a plane frame is presented, where the constituent members are considered to have a uniform distribution of mass and the effects of axial load, rotatory inertia and shear deflection, uniquely described by the parameters p, r and s, respectively, may be accounted for.

TL;DR: In this paper, a series of flow visualization photographs were taken during a portion of the shedding cycle and the observed flow field is compared with fluid velocity and cylinder motion measurements recorded simultaneously near the model.

TL;DR: In this paper, the influence of a finite cavity backing a finite panel on the transmission of sound through the panel and on the vibration of the panel was investigated, and a graphical technique, first used in a one-dimensional study of this case, was applied in the three dimensional case to predict frequencies of interest.

TL;DR: In this article, the effect of changes in duct wall acoustic properties on the transmission of sound through ducts was investigated and two special problems were considered: the first problem is that of a rectangular infinite-length duct with airflow and a single change in ductwall acoustic admittance; the second problem was that of an axisymmetric field in a finite circular duct without airflow and with an arbitrary number of duct wall admissible changes.

TL;DR: In this paper, the optimal attenuation rate for any mode pair in ducts of uniform rectangular, circular or annular cross-section was investigated for zero mean flow in the duct.

TL;DR: In this article, the authors developed the theory of a generalized Helmholtz resonator based on the jet-flow model, which is manifested in the nonlinearity of the orifice flow upon the passage of a high intensity wave.

TL;DR: In this article, a brief review of some of the relevant published literature is followed by a presentation and discussion of the experimental results obtained from the tests at BHRA, and possible mechanisms of excitation and stability criteria are proposed.

TL;DR: In this article, the effects of flexible boundaries on the normal modes and natural frequencies of low frequency sound transmission in cars are considered. But the authors focus on the case of a single enclosure with a flexible boundary and structural coupling between two enclosures allowing direct and flanking sound.

TL;DR: In this article, the effect of density on jet noise at low velocities was investigated at the SNECMA and NGTE using advanced research facilities, and it was shown that the noise data can be empirically correlated by using a velocity-dependent function of the fullyexpanded jet density.

TL;DR: In this article, a method of determining the effects of openings on the fundamental frequencies in plates with different types of boundary conditions is described, where the finite difference operators are developed for the reentrant corner, junction point, etc.

TL;DR: In this paper, it was shown that the simulated random processes are asymptotically Gaussian processes as the number of terms, N, of sine or cosine functions approaches infinity.

TL;DR: In this paper, measurements of the noise field from three 1.52, 2.4 and 2.84 inch diameter subsonic cold-air jets are presented in the anechoic chamber of National Gas Turbine Establishment, Pyestock, on a test rig with a very large contraction ratio (maximum 250:1, minimum 70:1).

TL;DR: In this paper, an analytical study of the modal field in sheared flow was conducted and it was shown that the pressure and normal particle displacement are constant through a boundary layer of arbitrary profile.

TL;DR: In this paper, a vibration analysis involving the use of complex Fourier series is described, by means of which the complete frequency eigenvalue spectrum and associated mode shapes for rotating axially, radially and torsionally prestressed cylindrical shells can be obtained.