## THERMAL SCIENCE

International Scientific Journal

### SECOND LAW ANALYSIS OF LAMINAR FORCED CONVECTION IN A ROTATING CURVED DUCT

**ABSTRACT**

In this paper, flow characteristics, heat transfer and entropy generation in a rotating curved duct are studied numerically. The continuity, Navier-Stokes and energy equations are solved using control volume method. The effects of Dean number, non-dimensional wall heat flux, and force ratio (the ratio of Coriolis to centrifugal forces) on the entropy generation due to friction and heat transfer irreversibility and also overall entropy generation are presented. Optimal thermal operating conditions (based on dimensionless parameters) are determined from the viewpoint of thermodynamics second law. The comparison of numerical results at different force ratios indicates that for any fixed Dean number or non-dimensional heat flux, the minimal frictional entropy generation occurs when the Coriolis and centrifugal forces have the same value but in the opposite direction. For a specific non-dimensional heat flux, there is a force ratio with maximum heat transfer irreversibility which depends on Dean number. Based on optimal analysis, the optimal force ratio with minimal total entropy generation depends on heat flux and Dean number.

**KEYWORDS**

PAPER SUBMITTED: 2012-06-06

PAPER REVISED: 2013-01-28

PAPER ACCEPTED: 2013-03-01

PUBLISHED ONLINE: 2013-04-21

**THERMAL SCIENCE** YEAR

**2015**, VOLUME

**19**, ISSUE

**1**, PAGES [95 - 107]

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