A generic microfluidic system composed by two single chamber valveless micropumps connected to a simple T-type channel intersection is examined numerically. The characteristics of a feasible valveless micropump have been used in the design, where efficient mixing is produced due to the pulsating flow generated by the micropumps. The advantages of using time pulsing inlet flows for enhancing mix...

BACKGROUND The traditional cyclone has been developed for the removal of airborne silica particles from local exhaust ventilation (LEV). The objective of this research was to evaluate the effects of velocity and particles load on efficiency of cyclone in the Stone Crushing Units at Azendarian Area. METHODS After the designing and installing the traditional cyclone, downstream and upstream sam...

The flow field development through a simplified shock absorber orifice geometry is investigated using single phase Large Eddy Simulation. Hydraulic oil used as the working fluid with constant inlet velocity and an open top boundary to allow study focus on free shear layer in vicinity of main orifice. validated standard mixing dynamics. impact shape discussed regards initial growth, potential ap...

Biogas biodesulfurization by an anoxic biotrickling filter packed with open pore polyurethane foam at the laboratory scale (packed volume 2.4L) has been studied. The biotrickling system was operated for 620 days with biogas supplied continuously and two nitrate feeding regimes were tested (manual and programmed). Biomass immobilization was carried out under the manual nitrate feeding regime and...

Spacers are used in spiral wound and plate and frame membrane modules to create flow channels between adjacent membrane layers and mix fluid within the flow channel. Flow through the spacer has a significant beneficial impact on mixing and resulting mass transfer rates but is accompanied by an undesirable increase in pressure drop. Computational Fluid Dynamics (CFD) is a common tool used to eva...

In this paper, a three-dimensional numerical model of transient incompressible gaseous flow in microchannels was established. The influence of changing the inlet velocity on the transient fluid flow is analyzed – using finite volume software (Fluent 6.3). The study showed that the transient period is decreased when the inlet velocity is increased, the maximum velocity is almost twice the entran...

First, in order to use as an inlet condition for turbulent simulation, a method is presented which produces numerically an artificial turbulence, namely, a series of velocity fluctuations of which frequency is Gaussian, and energy spectrum and root mean square correspond to the given ones. Besides, the fluctuation data are determined by the characteristic parameters of turbulent flows such as t...

This numerical study investigates the steady state natural convection of light and heavy water entering a vessel from the left and leaving on the right. The cavity consists of a matrix of cylindrical heated rods as in light and heavy water reactors. The aim of the study is to describe the effects of water inlet velocity on the flow and thermal fields in presence of such heated obstacle. The inv...

the effect of mixing on rheological behavior of 6% wt epoxy-clay nanocomposites was studied. the mixing processes were carried out by low shear mixer, homogenizer and ultrasonic and combination of different mixing techniques at medium and maximum power. all these methods led to intercalated structure. the xrd results showed that the ultrasonic has the best effect on dispersion while a low shear...