In this work, extraction of propionic acid from the aqueous phase to the organic phase (1-octanol) was performed in T-junction microchannels and effects of channel diameter and fluid flow rate on the mass transfer characteristics were investigated. The two-phase flow patterns in studied microchannels with 0.4 and 0.8 mm diameters were observed. Weber ‎ number and surface-to-volume ratio were ca...

the unsteady free convection flow between two long vertical parallel plates withvariable temperature and mass diffusion in the presence of the thermal radiation hasbeen presented. the governing dimensionless coupled linear partial differentialequations on the flow are solved by using the laplace transform technique. theexact solutions have been obtained for the fluid velocity, temperature and t...

A numerical model is developed to simulate the transport phenomena in the flow channel between parallel plates with porous and non-porous (or impermeable) walls. The continuity and momentum equations were solved first, assuming the wall Reynolds number in the range of with the suction or injection of air at a speed equal to the uniform inlet velocity. The results show that at constant inlet and...

Heat transfer coefficients were measured in a circular tube with dimpled surface. The almond type dimples were fabricated, the tube diameter (D) 19mm and dimple depth 3 mm ratio was kept constant, while holding diameter 10mm of dimple is required length 21.5mm because of the elongated shape. The Reynolds number based on the channel hydraulic diameter was varied from 25000to 95000. An experiment...

This computational fluid dynamic analysis attempts to simulate the incompressible steady fluid flow and heat transfer in a solar air channel with wall-mounted baffles. Two ꞌSꞌ-shaped baffles, having different orientations, i.e., ꞌSꞌ-upstream and ꞌSꞌ-downstream, were inserted into the channel and fixed to the top and bottom walls of the channel in a periodically staggered manner to develop vorti...

the aim of this study was to investigate the rate of water vapor permeability (wvp) and moisture sorption of starch-montmorillonite (mmt) nanocomposite films. the nanocomposite films were prepared using the casting method andglycerol was used as a plasticizer. the effect of glycerol concentration on wvp of the films was determined at 25°c with a relative humidity of 0-99% (inside and outside of...

the effects and influences of various parameters upon the efficiency and the overall volumetric mass transfer coefficients are important subjects to be studied in most liquid-liquid extraction processes. one of these important parameters is surface active agent (surfactant). in this paper, in order to study the effect of sodium dodecyl sulfate (sds) concentration on the efficiency and the avera...

this paper presents a numerical study of local mass transfer coefficients in a 90° bend using the rng version of k–e model to include the influence of curvature on the turbulent transport. simulations were performed for flow through a 90°, 3-d bend for reynolds numbers of 13500, 90000, and 390000, schmidt numbers of 2.53 and 700 and curvature ratios of 1.5, 2, and 2.5. the differences between t...

in this numerical study the the heat transfer and laminar nanofluid flow in the three-dimensional microchannels with triangular cross-section is simulated. for increase the heat transfer from the walls of the channel, semiattached & offset mid- truncated rib,s placed in the canal, and the tooth geometry and the impact is studied. in this study, the water is base fluid, and the influence of the ...