investigations on vibration behaviors of railway track systems were attempted in this research. this was made by conducting a comprehensive field investigation into the free vibration of track systems and response of tracks to train moving loads. in-situ modal analysis was used in a railway track field as an efficient method of investigating dynamic properties of railway track systems. natural ...

in the present paper, the modal analysis on a full finite element model of an off-road vehicle. this vehicle was modeled in the catia software and then meshed in the hypermesh software. the free vibration analysis was conducted by the abaqus software. by applying an external displacement, the forced vibration analysis was also performed. as a result, natural frequencies and shape modes were ext...

in this paper, a simple and efficient method for modeling and solving the equations of a rotor with any number of disks, bearings and mass unbalances is presented using the assumed modes method. this model consists of a continuous shaft, arbitrary number of mass unbalances in any axial location and phase angle, and any number of rigid disks and bearings. this arrangement is extensively used in ...

in this paper, the effects of transverse cracks on rotating shaft were studied. according to earlier works, crack shaft failure decrease the critical speed of the shaft and also exhibit a nonlinear vibration behaviour leading to increases the amplitude of 1x and 2x harmonics (first and second order of rotational speed in torsional vibration). this suggests that the application of order analysis...

This paper presents eigensolution and non-modal analyses for immersed boundary methods (IBMs) based on volume penalization the linear advection equation. approach is used to analyze behavior of flux reconstruction (FR) discretization, including influence polynomial order parameter numerical errors stability. Through a semi-discrete analysis, we find that inclusion IBM adds additional dissipatio...

The Lam and Rott theory of linearized unsteady boundary layers is revisited, and some new results are obtained. The exact outer eigensolution for a flat plate found in the original paper is shown to be a special case of the Prandtl transposition theorem. The streamwise coordinate-dependent factor of the inner eigen-solutions, first found by M. E. Goldstein for the flat plate, is generalized for...

In this work we consider the numerical computation of eigenpairs of a matrix derived from integral operators. The matrix is associated to a radiative transfer problem in stellar atmospheres that is formulated by means of a weakly singular Fredholm integral equation defined on a Banach space. We examine direct and iterative parallel strategies for the eigensolution phase, using state-of-the-art ...

abstract: in this paper, nonlocal euler–bernoulli beam theory is employed for transverse vibration analysis of an initially pre-stressed size-dependent rotating nanotube. the nonlocal eringen theory takes into account the effect of small size, which enables the present model to become effective in the analysis and design of nanosensors and nanoactuators. governing equations are derived through ...

vibration in the air slide tables of ultra precision machines prevents gaining accuracies within nanometer level. in this work, dissimilar types of internal vibration including small vibrations and pneumatic hammers have been tested and some measures have been offered to reduce their effects. this paper has also proceeded to the vibration tests on the air slide tables built with different numbe...