The basic concept of dynamic characteristics of spindle is introduced. The first ten order vibration mode and natural frequency of shaft are obtained by modal analysis and harmonic response analysis using software ANSYS. The deformation trend of spindle under resonance state is analysed and the contrast between theory and simulation critical speed is done. The frequency response curve of spindl...

We study the neutrino oscillation problem in the framework of the wave packet formalism. The neutrino state is described by a packet located initially in a region S (source) and detected in another region D at a distance R from S. We examine how the oscillation probability as a function of variable R can be derived from he oscillation probability as a function of time t, the latter being found ...

The upscale CNC machine is the research object, the magnetic levitation bearing technology which is suitable to AMB spindle and guide are researched. On the basis of the structure and working principle of AMB and the stiffness and damping characteristics, the performance of electromechanical coupling dynamics is studied according to the theory of traditional dynamics and the characteristics of ...

Aerodynamic bearings with elastically supported tilting pads have operational properties comparable with widely-used foil journal bearings. They combine the excellent stability of tilting pad bearings, as a result of very small cross-coupling stiffness terms, with the positive properties of foil bearings, namely their ability to adapt to changing operating conditions and presence of additional ...

Catcher bearings (CB) are an essential component for rotating machine with active magnetic bearings (AMBs) suspensions. The CB’s role is to protect the magnetic bearing and other close clearance component in the event of an AMB failure. The contact load, the Hertzian stress, and the sub/surface shear stress between rotor, races, and balls are calculated, using a nonlinear ball bearing model wit...

In order to study the dynamic response of LNG storage tank under action seismic load and isolation effect lead-core rubber bearing, this paper establishes experimental model with reference structural form large-scale tank, test is obtained using a shaking table test. Simplified mechanical models non-isolated isolated tanks are proposed responses corresponding calculated Newmark-beta method. Und...

In this paper, a new method for the balancing of rotor-bearing systems supported on fluid film bearings is proposed. The influence coefficients necessary are calculated using novel simulation called Numerical Assembly Technique. advantages approach quasi-analytical solutions equations motion complex and very low computation times. Technique extended by speed-dependent stiffness damping approxim...

local site conditions have a strong effect on ground response during earthquakes. two important soil parameters that control the amplification effects of seismic motions by a soil column are the soil hysteretic damping ratio and shear wave velocity. this paper presents the results of in situ damping ratio measurements performed using continuous surface wave attenuation data at a site in semnan ...

This paper investigates the static and dynamic characteristics of precision hydrostatic spindle with a mid-thrust bearing under different working conditions. Firstly, establishes fluid governing equations coupled journal thrust bearings based on orifice restrictors; Reynolds are solved using perturbation finite difference methods to obtain steady transient pressure distribution functions. Then ...

damping of a full-scale cable with a pair of passive–on magnetorheological (mr) dampers was tested. a cable of 215.58m long with the first mode frequency of 0.658hz was tensioned horizontally in cable prefabrication factory. two mr dampers were attached to the cable in an angle in the plane perpendicularly to the cable axis in 5m length from the cable anchorage. the applied voltage level was 0v...