the olefins polymerization process in a slurry reactor is discussed. the reaction rate dynamics was analyzed and the contributions of feed flow, gas-liquid mass transfer, polymerization reaction, and catalyst deactivation were estimated. the propylene solubility in a solvent mixture “heptane” was calculated using soave-redlich-kwong equation of state. these data were then approximated by henry-...

In this paper, we have considered the problem of rotating, magnetohydrodynamic heat and mass transfer by free convective flow past an exponentially accelerated isothermal vertical plate in the presence of variable mass diffusion. While the temperature of the plate is constant, the concentration at the plate is considered to be a linear function with respect to time t. The plate is assumed to be...

This article investigates the influence of cross-diffusion on the viscous fluid flow over a porous sheet stretching exponentially by applying the convective thermal conditions. Velocity slip at the boundary is considered. The numerical solutions to the governing equations are evaluated using successive linearisation procedure and Chebyshev collocation method. It is observed from this study that...

The effect of γ-Al2O3 nanoparticles on heat transfer rate, baffle spacing and pressure drop in the shell side of small shell and tube heat exchangers was investigated numerically under turbulent regime. γ-Al2O3-water nanofluids and pure water were used in the shell side and the tube side of heat exchangers, respectively. Since the properties of γ-Al2O3-water nanofluids were variable, they were ...

In the present study, the effect of various nanofluids on mass transfer coefficients in an irregular packed liquid-liquid extraction column was investigated. The chemical system of toluene–acetic acid–water was used. 10 nm SiO2, TiO2 and ZrO2 nanoparticles with various concentrations were dispersed in toluene-acid acetic to provide nanofluids. The influence of concentration and hydrophobicity/h...

The development of high-performance thermal systems has increased interest in heat transfer enhancement techniques. The application of additives to heat transfer liquids is one of the noticeable effort to enhance heat transfer. In this paper two-dimensional unsteady incompressible nanofluid flow in a confined jet at the laminar flow regime is numerically investigated. The Mixture model is consi...

In order to improve the efficiency and rate of heat transfer in heat exchangers, various techniques such as increasing the heat transfer coefficient are proposed. This study is devoted to the investigation of heat transfer coefficient variations due to the addition of CuO, TiO2 and CuO/TiO2 nanoparticles into a shell and tube heat exchanger. CuO/TiO2 nanocomposite was synthesized using mechanic...

We study microreactors with internal fields of posts as typical examples of structured microreactors to elucidate flow fields and their implications for mass transfer. Laser-induced fluorescence (LIF) visualization combined with image analysis is used to systematically quantify key features such as interfacial area, phase holdup and the characteristics of the post-wetting layer. The subsequent ...

Perturbation chromatography with multi component gas carrier and non-equilibrium thermodynamics liner law was applied for discussion of the interference effect and the displacement effect on mass transfer in multi component gas adsorption. Moment analysis method and stop & go simulation method were utilized to obtain each mass transfer parameters of adsorbate gases. Dependency of micropore diff...

electrochemical impedance spectroscopy (eis) is a suitable and powerful diagnostic testing method for fuel cells (fcs) since it is non-destructive and provides useful information about fc performance and its components. in this study, for the first time, a 500w cascade type 4 cells stack with integrated humidifier, water separator and internal manifolds was designed, fabricated and tested. the ...