Abstract

This paper uses the entropy generation minimization (EGM) method to optimize a single-phase, convective, fully developed flow with uniform and constant heat flux. For fixed mass flow rate and fixed total heat transfer rate, and the assumption of uniform and constant heat flux, an optimal Reynolds number for laminar and turbulent flow is obtained. The study also compares optimal Reynolds number and minimum entropy generation for cross sections: square, equilateral triangle, and rectangle with aspect ratios of two and eight. The rectangle with aspect ratio of eight had the smallest optimal Reynolds number, the smallest entropy generation number, and the smallest flow length.

Issue Section:
Technical Notes
Keywords:
minimum entropy methods, convection, mass transfer, laminar flow, turbulence, pipe flow
Topics:
Entropy, Heat flux, Heat transfer, Reynolds number, Turbulence, Flow (Dynamics), Laminar flow, Internal flow

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 by American Society of Mechanical Engineers
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