https://doi.org/10.1140/epjp/i2019-12481-9
Regular Article
Pulsatile flow and heat transfer of shear-thinning power-law fluids over a confined semi-circular cylinder
Department of Chemical Engineering, Indian Institute of Technology Roorkee, 247667, Roorkee, India
* e-mail: amitdfch@iitr.ac.in
Received:
19
February
2018
Accepted:
17
December
2018
Published online:
12
April
2019
This work is an attempt to simulate the effects of pulsating flow upon the thermal and hydrodynamic behavior of shear-thinning non-Newtonian fluid (approximated as power-law fluid) while it flows past a semi-circular cylinder fixed in a symmetrically confining channel and deduces the optimum oscillating frequencies and amplitude for a particular power-law index (n) and Reynolds number (Re). The semi-circular cylinder studied has a fixed temperature while the wall confinement is insulating. The ranges of control parameters varied are 
-100 (based on object's diameter), the amplitude of oscillation (A) = 0-0.6, the Strouhal number (St) = 0-2 and the n ranging from 0.2 to 1. The Prandtl number has been kept fixed at 
(which corresponds to several fluids of industrial importance like n-butanol, etc.). The isotherms and streamlines give a qualitative insight into the heat and flow transfer behavior as various parameters are varied, while the Nusselt number, overall drag and lift coefficients have been calculated to get a quantitative insight. Further, the augmentation in heat transfer and the decline in drag upon using a pulsating non-Newtonian fluid inlet as opposed to using a steady Newtonian flow have been established. Lastly, the temporal variations and the frequency of vortex shedding have been studied using a fast Fourier transform.
© Società Italiana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature, 2019
