Showing papers on "Rotary inertia published in 1989"
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TL;DR: In this paper, the free vibration characteristics of laminated composite shells are presented using an isoparametric doubly curved quadrilateral shear flexible element and first-order shear deformation theory is accounted for using an extension of Sanders' shell theory.
95 citations
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TL;DR: In this article, a refined higher-order theory for free vibration analysis of unsymmetricaliy laminated multilayered plates is presented, which accounts for parabolic distribution of the transverse shear strains through the thickness of the plate and rotary inertia effects.
92 citations
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TL;DR: In this article, the authors present a concise yet comprehensive method for the determination of natural frequencies of stiffened circular cylindrical shells based on the formulation of an energy functional which includes energy of bending in two planes and rotary inertia of the stiffeners.
79 citations
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TL;DR: In this article, a C0 finite element formulation of the higher-order theory is used to determine the natural frequencies of isotropic, orthotropic and layered anisotropic composite and sandwich plates.
Abstract: A C0 finite element formulation of the higher-order theory is used to determine the natural frequencies of isotropic, orthotropic and layered anisotropic composite and sandwich plates. The material properties that are typical of high modulus fibre reinforced composites are used to show the parametric effects of plate aspect ratio, length-to-thickness ratio, degree of orthotropy, number of layers and lamination angle/scheme. The present theory is based on a higher-order displacement model and the three-dimensional Hooke's laws for plate material. The theory represents a more realistic quadratic variation of the transverse shearing strains and linear variation of the transverse normal strains through the plate thickness. A special mass matrix diagonalization scheme is adopted which conserves the total mass of the element and includes the effects due to rotary inertia terms. The results presented should be useful in obtaining better correlation between theory and experiment, and to numerical analysts in verifying their results.
61 citations
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TL;DR: In this article, a closed-form solution was derived for the displacement and velocity space-time correlation function of the Bresse-Timoshenko beam with transverse damping, generalizing the corresponding result by Eringen for the classical Bernoulli-Euler beam.
50 citations
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TL;DR: In this article, a finite element analysis of orthogonally stiffened shells of revolution has been presented by combining a recently proposed shell of revolution element and a curved beam element, in which the effects of shear deformation and rotary inertia have been taken into account.
48 citations
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01 Jan 1989
TL;DR: In this article, the effects of temperature and acoustic loading are included in a theoretical finite element large deflection formulation for thin, isotropic beams, and the nature of the loads leads to the solution of two separate problems.
Abstract: The effects of temperature and acoustic loading are included in a theoretical finite element large deflection formulation for thin, isotropic beams. Thermal loads are applied as steady-state temperature distributions, and acoustic loads are taken to be ergodic and Gaussian with zero mean and uniform magnitude and phase along the length of the beam. Material properties are considered presently to be independent of temperature. Also, inplane and rotary inertia terms are assumed to be negligible, and all inplane edge conditions are taken to be immovable. For the random response analysis, both auto- and cross-correlation terms are included. The nature of the loads leads to the solution of two separate problems. First, the problem of thermal postbuckling is solved to determine the deflections and stresses due to the thermal load only. These deflections and stresses are then used as initial deflections and stresses for the random vibration analysis. Root-mean-square (RMS) maximum deflections and strains are obtained and compared with previous classical equivalent linearization results.
38 citations
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TL;DR: In this paper, a 24-dofisoparametric finite element has been presented for the analysis of generally laminated curved beams, and the effects of shear deformation and rotary inertia have been accounted for using the shear deformability theory which employs nonlinear shear strain variation across the section.
34 citations
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TL;DR: In this article, the authors present design equations and techniques for the complete shaking force and shaking moment balancing of four types of six-bar linkages due to both linear and rotary inertia, but excludes external loads.
29 citations
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TL;DR: In this article, a comprehensive computer algorithm used in the dynamic analysis of multibody systems is presented, which combines Kane's equations, the strain energy, and modal analysis to describe the elastic bodies.
Abstract: A comprehensive computer algorithm used in the dynamic analysis of multibody systems is presented. The procedures developed combine Kane's equations, the strain energy, and modal analysis to describe the elastic bodies. The equations of motion are expressed in a form in which their coefficients are based on the partial velocity and partial angular velocity arrays and are easily coded for computers. The nonlinear geometric stiffness matrix is developed for three-dimensional beams that account for the couplings between the deformation components having significant effects in high-speed systems. The method presented in this paper is tailored for structures with variable cross-sectional beam elements such as spacecraft antennae, helicopter rotor blades, robot systems, and mechanisms. The effects of rotary inertia as well as shear deformation are automatically included into the equations of motion. A method for obtaining the shape function matrix consisting of assumed dynamic modes is also presented. In addition, the preceding formulations are used in a simulation of a space-based robotic manipulator, and the results are compared with those obtained by Kane et al. in Ref. 20.
29 citations
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TL;DR: In this article, a 64-dof isoparametric quadrilateral finite element is presented for the analysis of generally laminated shells of revolution, and the effects of shear deformation and rotary inertia are accounted for by using shear deformations theory that employs the parabolic shear strain variation across the thickness.
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TL;DR: In this paper, a Vlasov type thin-walled beam theory with the effects of flexural-torsional coupling, transverse shear deformation and rotary inertia included is developed for the free vibration analysis of curved thinwalled beams with arbitrary open cross section.
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TL;DR: In this article, a finite element method based on Mindlin's theory is employed in the prediction of the dynamic transient response of multilayered composite sandwich plates, and numerical convergence and stability of 4noded linear, 8-noded serendipity, and 9noded Lagrangian elements are established using an explicit time integration technique.
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TL;DR: In this article, a numerical solution for geometrically nonlinear free vibrations of multispan beams on elastic supports is presented, where the horizontally and rotary inertia forces have been neglected and the beams are considered as distributed mass systems.
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TL;DR: In this paper, a method based on the variational procedure in conjunction with the finite difference technique is used to determine the natural frequencies and mode shapes of rectangular plates by including the effect of transverse shear deformation and rotary inertia.
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TL;DR: In this article, the dynamic response of anisotropic laminated composite plates to stationary random excitation is analyzed in terms of mean-squares and angle-dependent meansquares, as well as the obtained response characteristics may be useful in the design of composite plates subjected to random pressure fields.
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TL;DR: In this paper, the dynamic response of an imperfectly bonded buried orthotropic pipeline subjected to p-wave excitation has been investigated, where an infinite cylindrical shell model including the rotary inertia and shear deformation effects was used for the pipeline.
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12 Dec 1989
TL;DR: In this paper, a rotary field pole is fixed integrally rotatably to a drive plate for coupling the output shaft of an engine with a transmission, through a field core section secured to the engine body.
Abstract: PURPOSE:To improve the acceleration response of an engine, by exciting a rotary field pole fixed integrally rotatably to a drive plate for coupling the output shaft of the engine with a transmission, through a field core section secured to the engine body CONSTITUTION:Output shaft 3 of an engine 1 drives an automatic transmission 5 through a drive plate 14 the transmission 5 comprises a case 6 having a sleeve 6a extending to the engine 1 side and an input shaft 7 facing the output shaft 3 The rotary field pole 20 of a charge generator 19 is fixed to the drive plate 14 and rotated integrally with the engine 1 A field core section 24 comprising a field core 25 and a field coil 26 for exciting the rotary field pole 20 is secured to the engine 1 body not to rotate therewith By such arrangement, rotary inertia of the engine 1 is reduced and the acceleration response of engine is improved
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TL;DR: In this article, the axisymmetric free vibration and dynamic response of polar orthotropic clamped hemispherical shells subjected to suddenly applied loads, including idealized step pressure, a rectangular pressure impulse of finite duration and realistic blast pressure over the total or partial area were studied.
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TL;DR: In this paper, the combined effect of rotary inertia, shear deformation and root flexibility on the vibration characteristics of cantilever beams is investigated experimentally, and linear relationships are deduced for the reduction of frequencies.
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TL;DR: In this paper, a perturbation technique is used to study the effects of in-plane inertia, rotary inertia, and shear deformation on the nonlinear free vibration response of an imperfect, inplane loaded orthotropic plate.
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25 Apr 1989
TL;DR: In this paper, the moment of inertia H i of a body in rotation initially in rotation approximately about its principal axis of inertia Z into any given orientation H F one applies transversely to the axis Z three torque impulses in a plane containing H i and H F, the first for a time T 1, such that, at the end of one rotation of a satellite about itself, the axisZ shifts to Z 1 in the plane bisecting H i, whilst the kinetic moment moves to H 1, the second impulse at the instant when the principal axis is at Z 1
Abstract: In order to shift the moment of inertia H i of a body in rotation initially in rotation approximately about its principal axis of inertia Z into any given orientation H F one applies transversely to the axis Z three torque impulses in a plane containing H i and H F , the first for a time T 1 , such that, at the end of one rotation of a satellite about itself, the axis Z shifts to Z 1 in the plane bisecting H i and H F , whilst the kinetic moment moves to H 1 , the second impulse at the instant when the principal axis of inertia is at Z 1 for a time T 2 appropriate to shift the kinetic moment into a position H 2 symmetrical with H 1 with respect to this bisecting plane, and the third impulse at the instant when the principal axis of inertia is parallel to H F for a duration equal to T 1 .
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TL;DR: In this article, the virtual work theorem is used to derive the equations of motion for antisymmetric cross-ply laminates in a general state of nonuniform initial stress, where the effects of transverse shear and rotary inertia are included, and the equations are adjusted to a generic form by using appropriate transformations.
Abstract: Equations of motion for antisymmetric cross-ply laminates in a general state of nonuniform initial stress, where the effects of transverse shear and rotary inertia are included, are derived by the virtual work theorem. The equations are adjusted to a generic form by using appropriate transformations. With the help of using the transforma tions, introducing generalized parameters, and employing a similarity parameter, compre hensive solutions are found to this problem; hence, the curves presented in the text are generic rather than specific. The thick plate equations are solved for simply-supported rec tangular antisymmetric cross-ply laminated plates in a state of uniform compressive stress plus a uniform bending stress with both acting in the same direction. The results of the reduced set of equations agree with those obtained by previous investigators.
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TL;DR: In this paper, a finite element analysis of an orthogonally stiffened annular sector plate is presented by combining the annular sectors plate element and the curved beam element, in which the effects of shear deformation and rotary inertia have been taken into account.
Abstract: The finite element analysis of an orthogonally stiffened annular sector plate is presented by combining the annular sector plate element and the curved beam element. The plate and the curved beam elements are the isoparametric elements in which the effects of shear deformation and rotary inertia have been taken into account. In addition, both these elements are meant to be used for arbitrarily laminated structures and they are based on the higher order theories previously presented for plates, shells, and beams. Numerical results are presented to demonstrate the accuracy and correctness of the present finite element procedure for stiffened plates. Numerical results obtained on circumferentially stiffened sector plates illustrate the accuracy of an equivalent orthotropic plate (EOP) model and the plate‐stiffener system (PSS) model. The limitations of modeling the plate by thin plate elements and stiffeners by thin beam elements are also discussed.
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01 Feb 1989
TL;DR: In this paper, the authors proposed a utility model of a wind wheel structure of perpendicular axle wind motor in the shape of a cylinder, which is suitable for civilian generate electricity by wind force, hydraulic power and wind power generation in high-rise building, ship and cars, etc.
Abstract: The utility model belongs to a wind wheel structure of perpendicular axle wind motor. The structure is in the shape of a cylinder. The inner wall of the cylinder has 3-4 intra vanes and external wall of the cylinder has 3-4 gathering wind cover. The diameter of the cylinder is about 0.30-1.50 meter. The cylinder optimally made by aluminium alloy thin slab. The utility model has the advantages of simple and firm structure, long service life, stable and safe operation, little space occupation, higher rotation speed, larger rotary inertia, larger relative power output. The device is suitable for civilian generate electricity by wind force, hydraulic power and wind power generation in high-rise building, ship and cars, etc.
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TL;DR: A procedure is described and a FORTRAN program presented for the evaluation of the reduced moment of inertia for internal rotation in a molecular system consisting of a rigid frame and one asymmetric top.
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15 Jun 1989-JSME international journal. Series 3, Vibration, control engineering, engineering for industry
TL;DR: In this paper, a modified averaging approach to the solution for the dynamic performance of an externally pressurized, gas-lubricated, circular thrust bearing in a laminar flow regime, is presented under the assumption of a small harmonic vibration.
Abstract: In this report, the modified averaging approach to the solution for the dynamic performance of an externally pressurized, gas-lubricated, circular thrust bearing in a laminar flow regime, is presented under the assumption of a small harmonic vibration. This approach can evaluate the inertia effects under highly unsteady conditions. The accuracy of the approximate solutions presented in a previous report are compared and evaluated under similar conditions and the following conclusions are obtained: (1) The conventional averaging approach, in which all the inertia terms are averaged out across the film thickness, gives a good approximation. (2) The first-order solution of the perturbation method becomes remarkably inaccurate as the unsteadiness becomes high.
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TL;DR: In this article, a theoretical solution for the reflection and transmission of flexural waves at a discontinuity of cross section is presented, based on the Timoshenko beam theory, which takes into account the effects of shear deformation and rotary inertia.
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20 Sep 1989
TL;DR: In this paper, the permanent magnet installation skeleton of the rotor of the utility model, comprising two end locating rings and at least one middle localization ring, is dismountedable, the localization spokes of the localization rings are hollow and quite short.
Abstract: The utility model relates to a rotor for permanent-magnet excited motor. In the prior art, the permanent magnet localization skeleton of the rotor is designed as an integral structure, which causes that the manufacturing cost is high and the rotary inertia of the rotor is large. The permanent magnet installation skeleton of the rotor of the utility model, comprising two end locating rings and at least one middle localization ring, is dismountable, the localization spokes of the localization rings are hollow and quite short, and a plurality of permanent magnet installation grids are formed between the localization spokes. The rotational inertia of the utility model is small, the installation of the permanent magnet is convenient and accurate, and the manufacturing cost is cheap.