the use of bio-ethanol as an alternative diesel engine fuel is rapidly increasing. bio-ethanol is mixed with diesel fuel at different ratios and used in ci and si engines. since vibrations have direct effects on users and engine components, for this reason analysis of vibration resulting from combustion in ci engines is very important. in this study, evaluation of vibration was performed for bo...

The use of distinguishable complex vibrations that have multiple spectral components can improve the transfer of information by vibrotactile interfaces. We investigated the qualitative characteristics of dual-frequency vibrations as the simplest complex vibrations compared to single-frequency vibrations. Two psychophysical experiments were conducted to elucidate the perceptual characteristics o...

Acoustic stimulation is a promising method for increasing drainage of non-Newtonian fluids through porous structures in various applications. In this study, a mathematical model is developed for unsteady flow of a bi-viscous incompressible fluid in a circular straight channel. Longitudinal vibrations are superimposed on the flow driven by changing pressure gradients along the channel. Simulatio...

6 The dynamics of heterogeneous materials, like rocks and concrete, is complex. It includes such features as nonlinear elasticity, hysteresis, and long-time relaxation. This dynamics is very sensitive to microstructural changes and damage. The goal of this paper is to propose a physical model describing the longitudinal vibrations in heterogeneous material, and to develop a numerical strategy t...

Wheelchair users rely on their wheelchairs for mobility for extended periods of time every day. According to the International Standards Organization 2631-1 standard on human vibration, individuals in a seated position when exposed to whole-body vibrations (WBV) are at risk of injury. This study evaluated vibration exposure during manual and power wheelchair driving over nine sidewalk surfaces ...

Chatter vibrations are present in almost all cutting operations and they are the major obstacles in achieving desired surface finish. Chatter vibrations are the self excited vibrations, which has an adverse effect on surface roughness, dimensional accuracy of the machined components. This paper investigates the occurrence of regenerative chatter vibrations in centerless bar turning operation. T...

in this paper deflection and free vibration of sandwich panel is studied. the core of sandwich panels is made of hexagonal honeycomb and faces are made of two different materials of carbon fiber reinforced plastic and k-aryl/epoxy covering. the governing equations are deduced from the first order sheer deformation theory (fsdt) and they are solved using generalized differential quadrature metho...

In this paper, we have considered an inhomogeneous beam with a damping distributed along the length of the beam. The beam is clamped at both ends and is assumed to vibrate longitudinally. We have estimated the total energy of the system at any time t. By constructing suitable Lyapunov functional, it is established directly that the energy of this system decays exponentially.

For a simply supported Bernoulli-Euler beam under moving load with constant velocity the bending and torsion vibrations are analysed. An analytical solution of decoupled partial differential equations is derived based on eigenmode expansion considering boundary initial conditions. pure analysis performed calculated. various longitudinal speeds results plotted. The coupled deformations computed ...

An efficient and modular numerical prediction model is presented to predict vibrations and re-radiated noise in buildings due to metro trains. The approach comprises of three weakly coupled problems: the dynamic vehicle-track-tunnel-soil interaction problem, the dynamic soil-structure interaction problem and the calculation of the acoustic response inside the rooms. The three-dimensional dynami...