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Abstract

The characteristic of nano sized particles mass flux conditions are engaged in this investigation. Here we assume that the nano sized particle flux is zero and the nano sized particle fraction arranged itself on the boundary layer. With this convincing and revised relation, the features of Buongiorno relation on three-dimensional flow of Carreau fluid can be applied in a more efficient way. The governing partial differential equations of continuity, momentum, energy and concentration equations which are transmitted into set of pair of nonlinear ordinary differential equations utilizing similar transformations. The numeric solutions are acquired by engaging the bvp4c scheme, which is a finite-difference code for solving boundary value problems. A parametric study is accomplished to demonstrate the impact of Prandtl number,Weissenberg numbers, radiation parameter, chemical reaction parameter, thermophoresis parameter, Brownian motion parameter and Lewis number on the fluid velocity, temperature and concentration profiles as well skin friction coefficient, Nusselt number and Sherwood number within the boundary layer. From this we find the way in which magnetic parameter contributes to the increase in local skin fraction, and the decrease in the Nusselt and Sherwood numbers in these cases. The effects of the velocity temperature and concentration profile are obtained and presented graphically.

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Authors and Affiliations

B. Madhusudhana Rao
Degavath Gopal
Naikoti Kishan
Saad Ahmed
Putta Durga Prasad
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Abstract

Efficiency of agitation was considered for different physical systems on the basis of our own experimental studies on homogenisation, heat and mass transfer as well as gas hold-up. Measurements were performed for different physical systems: Newtonian liquids of low and higher viscosity, pseudoplastic liquid, gas–liquid and gas–solid–liquid systems agitated in vessels of the working volume from 0.02 m3 to 0.2 m3. Agitated vessels of different design were equipped with a high-speed impeller (10 impellers were tested). Comparative analysis of the experimental results proved that energy inputs (power consumption) should be taken into account as a very important factor when agitation efficiency is evaluated in order to select a proper type of equipment. When this factor is neglected in the analysis, intensification of the process can be estimated only.
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Authors and Affiliations

Joanna Karcz
1
Jolanta Szoplik
1
ORCID: ORCID
Marta Major-Godlewska
1
Magdalena Cudak
1
Anna Kiełbus-Rapała
1

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, al. Piastów 42, 71-065 Szczecin, Poland

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