This paper studies the propagation of shear waves in a composite structure consisting of a piezoelectric layer perfectly bonded over a micropolar elastic half space. The general dispersion equations for the existence of shear waves are obtained analytically in the closed form. Some particular cases have been discussed and in one special case the relation obtained is in agreement with existing r...

This study is concerned with the prediction of particles’ velocity in a dilute turbulent gas-solidboundary layer flow using a fully Eulerian two-fluid model. The closures required for equationsdescribing the particulate phase are derived from the kinetic theory of granular flows. Gas phaseturbulence is modeled by one-equation model and solid phase turbulence by MLH theory. Resultsof one-way and...

background: an imbalance of the cerebrovascular response during functional activation of the brain has been postulated as a factor in the pathophysiology of migraine. the purpose of this study was to determine the transcranial doppler sonography (tds) diagnostic value for the cerebral flow velocity changes in the interictal phase of classic migraine. methods: this study was carried out on 46 pa...

In the most application of nozzle with gas-liquid two-phase flow, the quality of mixture in exhaust of nozzle is the most important parameter as well as the flow velocity. On the other hand, in some industrial application, such as water injection in forced induction (turbocharged or supercharged) internal combustion engine the spray quality is the main goal of designing. In this case and for im...

Background: Balance disorder is one of the most-studied fields in low-back pain patients (LBP). However, there isinsufficient information regarding the effect of LBP subgrouping on postural control. The purpose of the present studywas to compare postural control between subgroups of chronic nonspecific LBP and healthy subjects during lifting.Methods: A total of 35 men with chronic LBP (19 activ...

sieve trays are widely used in the gas- liquid contactors such as distillation and absorption towers. in this article, a three-dimensional, two phase cfd model using euler-euler framework was developed to simulate a distillation tower with two sieve trays. hydrodynamic simulation of air and water system in different rates of gas phase was carried out and velocity distribution parameters, clear ...

In the present paper, the Zelt algorithm has been extended for ray tracing through an anisotropic model. In anisotropic media, the direction of the propagated energy generally differs from that of the plane-wave propagation. This makes velocity values to be varied in different directions. Therefore, velocity modeling in such media is completely different from that in an isotropic media. The vel...

In this study, the effect of operating parameters on dispersed phase holdup in liquid-liquid extraction process has been investigated. Three chemical systems (Toluene/Water, Butyl acetate/Water, and n-Butanol/Water) were utilized and holdup was considered in a wide range of interfacial tensions through a Scheibel extraction column. Various rotor speeds were examined on the certain velocities of...