## THERMAL SCIENCE

International Scientific Journal

### IMPACT OF SURFACE TEXTURE ON ENTROPY GENERATION IN NANOFLUID

**ABSTRACT**

We consider a heat transfer augmentation problem to minimize the entropy generation by assuming boundary-layer flow of nanofluid over a moving wavy surface. The nanofluid demonstrates great potential in enhancing the heat transfer process due to its high thermal conductivity. The famous Tiwari and Das model has been used in the present article. Two types of water based nanofluids containing Cu and Fe3O4 nanoparticles are considered. Moreover, the surface texture is taken to be sinusoidal wavy to improve the thermal contact. The governing equations are transformed into a system of non-similar PDE by using suitable dimensionless variables and solved by the Keller-Box method. The effects of involved parameters like amplitude wavelength ratio, group parameters, and volume fraction on the total entropy number and the Bejan number are analyzed graphically. It is showed Fe3O4 base nanofluid is more effective to lessen the entropy production as compared to Cu base nanofluid.

**KEYWORDS**

PAPER SUBMITTED: 2019-10-04

PAPER REVISED: 2019-12-07

PAPER ACCEPTED: 2019-12-11

PUBLISHED ONLINE: 2020-01-04

**THERMAL SCIENCE** YEAR

**2021**, VOLUME

**25**, ISSUE

**Issue 2**, PAGES [1171 - 1180]

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