**Mathematical Analysis of Entropy Generation in the Flow of Viscoelastic Nanofluid through an Annular Region of Two Asymmetric Annuli Having Flexible Surfaces**

**Arshad Riaz 1,\*, Ayesha Gul 1, Ilyas Khan 2,\*, Katta Ramesh 3, Sami Ullah Khan 4, Dumitru Baleanu 5,6,7 and Kottakkaran Sooppy Nisar <sup>8</sup>**


Received: 22 January 2020; Accepted: 25 February 2020; Published: 28 February 2020

**Abstract:** In this manuscript, the authors developed the mathematical model for entropy generation analysis during the peristaltic propulsion of Jeffrey nanofluids passing in a midst of two eccentric asymmetric annuli. The model was structured by implementation of lubrication perspective and dimensionless strategy. Entropy generation caused by the irreversible influence of heat and mass transfer of nanofluid and viscous dissipation of the considered liquid was taken into consideration. The governing equations were handled by a powerful analytical technique (HPM). The comparison of total entropy with the partial entropy was also invoked by discussing Bejan number results. The influence of various associated variables on the profiles of velocity, temperature, nanoparticle concentration, entropy generation and Bejan number was formulated by portraying the figures. Mainly from graphical observations, we analyzed that, in the matter of thermophoresis parameter and Brownian motion parameter, entropy generation is thoroughly enhanced while inverse readings were reported for the temperature difference parameter and the ratio of temperature to concentration parameters.

**Keywords:** entropy generation; Bejan number; nanoparticles; Jeffrey fluid model; peristaltic flow; analytical solutions; eccentric annuli
