Stretching process of sheet metals in both cases of axisymmetric and non-axisymmetric is analyzed. A rigid-plastic, normal anisotrop material is assumed and large strain formulation is applied. Triangular elements are used and stiffness equations of elements are obtained from virtual work principle. These nonlinear equations are linearized by Newton-Raphsons method and are solved by Gaussian el...

Tubular structures are widely used in infrastructure, especially for pipes and marine installations. Corrosion is a key damage type these structures, if undetected may cause structural deficiency or even collapse. This paper investigates the effects of localised corrosion on vibration properties axisymmetric tubular proposes novel baseline-free identification method to overcome fact that differ...

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...

We investigate some simple finite element discretizations for the axisymmetric Laplace equation and the azimuthal component of the axisymmetric Maxwell equations as well as multigrid algorithms for these discretizations. Our analysis is targeted at simple model problems and our main result is that the standard V-cycle with point smoothing converges at a rate independent of the number of unknown...

stretching process of sheet metals in both cases of axisymmetric and non-axisymmetric is analyzed. a rigid-plastic, normal anisotrop material is assumed and large strain formulation is applied. triangular elements are used and stiffness equations of elements are obtained from virtual work principle. these nonlinear equations are linearized by newton-raphsons method and are solved by gaussian el...

The purpose of this study is to determine more accurately the marginal stability condition for axisymmetric waves since it is believed that an unstable axisymmetric wave could affect the amplification of spiral waves. An axisymmetric wave with a gradient term of velocity dispersion ( surface density ) is derived. Analysis of this axisymmetric wave with a gradient term for our own galaxy shows t...