Showing papers in "Journal of Sound and Vibration in 1990"

TL;DR: In this article, the authors proposed a non-destructive testing method for crack identification, which requires amplitude measurements at two positions of the structure only and is applicable to all one-dimensional structures.

TL;DR: In this paper, a new structure (shell or plate) containing an integrated distributed piezoelectric sensor and actuator is proposed, where the distributed sensing layer monitors the structural oscillation due to the direct PDE and the distributed actuator layer suppresses the oscillation via the converse PDE.

TL;DR: In this paper, a digital simulation technique and the method of harmonic balance were used to develop steady state solutions for the internal sinuosidal excitations in a spur gear pair.

TL;DR: In this paper, an element stiffness matrix of a cantilever beam with a crack is derived from an integration of stress intensity factors, and then a finite element model of a cracked beam is established.

TL;DR: In this article, a bearing stiffness matrix of dimension six is proposed which clearly demonstrates a coupling between the shaft bending motion and the flexural motion on the casing plate, and a numerical scheme which involves a solution of non-linear algebraic equations is proposed for the estimation of the stiffness coefficients given the mean bearing load vector.

TL;DR: In this paper, the effect of a constant axial tensile force on natural frequencies and mode shapes of a uniform single-span beam, with different combinations of end conditions, is presented.

TL;DR: In this paper, a two source-location method was proposed for measurement of the four-pole or the transfer matrix parameters for an acoustic element or a subsystem of elements by means of four-microphone technique and use of the transfer function approach.

TL;DR: In this paper, the dynamic analysis of elastic beams subjected to dynamic loads induced by the arbitrary movement of a spring-mass-damper system is presented, and the governing equations for the interaction between the beam and the moving dynamic system are derived, based on a finite element formulation.

TL;DR: In this article, the authors demonstrate the feasibility of utilizing Shape Memory Actuators (SMA) in controlling the flexural vibrations of a flexible cantilevered beam, by using the finite element method, and integrated with the thermal and dynamic characteristics of SMA to develop a mathematical model of the composite beam-actuators system.

TL;DR: In this paper, an approximate Galerkin solution to the one-dimensional cracked beam theory developed by Christides and Barr for the free bending motion of beams with pairs of symmetric open cracks is suggested.

TL;DR: In this article, active control of sound radiation from vibrating plates by oscillating forces applied directly to the structure is analytically studied, and it is shown that global attenuation of broadband radiated sound levels for low to mid-range frequencies can be achieved with one or two control forces, irrespective of whether the system is on or off resonance.

TL;DR: In this paper, a series of in-flight experiments on the active contrl of propeller-induced passenger cabin noise in a B.Ae. 748 aircraft were presented. But the results were limited to the first three harmonics of the blade passage frequency.

TL;DR: In this paper, the free vibration problem of a homogeneous isotropic thick cylindrical shell or panel subjected to a certain type of simply supported edge boundary conditions is considered, and the governing equations of three-dimensional linear elasticity are employed and solved by using a new iterative approach which, in practice, leads to the prediction of the exact frequencies of vibration.

TL;DR: In this paper, an incremental harmonic balance (IHB) method is derived for a general system of differential equations with cubic nonlinearity, which governs a wide range of engineering problems such as large-amplitude vibration of beams or plates.

TL;DR: In this paper, the wave transmission coefficients of structural joints are calculated for a generic plate/beam junction, which consists of an arbitrary number of plates which are either coupled through a beam or directly coupled along a line, and due allowance is made for offsets between the plate attachment lines and the shear axis of the beam.

TL;DR: In this paper, the effects of a fluid load on a sandwich plate are analyzed and the effect of bending stiffness and loss factor not only depend on material parameters and plate geometries but also on frequency.

TL;DR: In this article, a theoretical model for the transmission of acoustic waves out of a semi-infinite circular jet pipe in the presence of subsonic flow out of the pipe is presented.

TL;DR: In this paper, two-dimensional airfoils with cubic pitching stiffness in incompressible flow are analyzed to investigate the chaotic behavior of self-excited dynamical system and a two-step approximate analysis gives some interpretation of the route to chaos for the airfoil system investigated.

TL;DR: In this article, a set of two-dimensional orthogonal plate functions is used as an admissible deflection function for the study of the flexural vibration of skew plates by the Rayleigh-Ritz method.

TL;DR: In this article, a statistical investigation of the effects of disorder on the dynamics of one-dimensional nearly periodic structures is presented, where the problem of vibration propagation from a local source of excitation is considered.

TL;DR: In this article, the authors measured the apparent mass of the seated human body with and without backrest contact for a range of three vibration magnitudes and found that the body appeared to have two heavily damped modes of vibration when there was no backrest contacts.

TL;DR: In this paper, the bearing stiffness matrix [ K ] bm is incorporated in discrete system models involving lumped parameter and finite element modeling techniques, and the stability issue associated with the proposed bearing model is addressed analytically by using Liapunov's stability method.

TL;DR: In this article, it was shown that the noise intensity depends only on the amplitude of the quasi-periodic shock cell structure and not on the strong first shock, which makes it possible to extend the noise prediction formulas by simply modifying the shock cell strength in the original formulas.

TL;DR: In this article, the concept of an equivalent imperfection mass is introduced to quantify the frequency splitting which occurs in slightly imperfect axisymmetric bodies, and the concept is used to estimate the trimming mass which must be added to or removed from the ring, and at which point, in order to reduce or eliminate the frequency split in a given pair of modes.

TL;DR: In this paper, a comparison between two periodic frequency-swept perturbation methods applied in identification of fluid forces of rotating machines is presented, based on the existence and strength of the circumferential flow most often generated by the shaft rotation.

TL;DR: In this article, the eigenvalue equation was derived analytically by using the expansion theorem and then numerically calculated eigenvalues and eigenvectors were calculated numerically.

TL;DR: In this paper, the effect of crack closure on the frequency changes of cracked cantilever beams was investigated by using both computer simulations and experimental modal analysis, and the results showed that, relying on the drop in the natural frequencies alone, especially the higher modes, may lead to serious underestimation of the crack severity.

TL;DR: In this paper, a derivation of the four-pole parameters including higher order mode effects, but with flow-acoustic interactions neglected, is presented for expansion chamber mufflers with extended inlet and outlet.

TL;DR: In this paper, the effects of simultaneous noise and vibration on subjective responses were investigated in three sessions during each of which they were presented with six levels of noise combined with six magnitudes of vibration, in all 36 combinations.

TL;DR: In this article, a powerful model for the analysis of the squealing noise of railway wheels is presented, which includes the entire path from the excitation to the human ear, and the dynamical behaviour of linear subsystems is specified uniformly by modal degrees of freedom.