## THERMAL SCIENCE

International Scientific Journal

### ENTROPY ANALYSIS IN MOVING WAVY SURFACE BOUNDARY-LAYER

**ABSTRACT**

It is a well-established fact that significant gain in the heat transfer rate can be obtained by altering that flat surface texture of the working body. The most convenient alteration, in view of mathematical handling, is the wavy one. Existing studies reveal that the convective heat transfer phenomenon is affected significantly due to the presence of a solid wavy surface. How does the phenomena of entropy generation is effected due to a wavy surface is the question investigated in this manuscript. The expressions for irreversibility distribution rate, Bejan number, and volumetric entropy generation number have been evaluated by Keller-Box method. The effect of important parameters of interest, such as wavy amplitude, Prandtl number, and group parameter on irreversibility distribution rate, Bejan number and entropy generation number, have been discussed in detail. The study reveals that entropy generation number decreases and irreversibility rate increases by increasing the amplitude of the wavy surface.

**KEYWORDS**

PAPER SUBMITTED: 2016-10-29

PAPER REVISED: 2017-02-13

PAPER ACCEPTED: 2017-02-25

PUBLISHED ONLINE: 2017-03-03

**THERMAL SCIENCE** YEAR

**2019**, VOLUME

**23**, ISSUE

**1**, PAGES [233 - 241]

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