Transient Analysis of Heat and Mass Transfer via Natural Convection over a Vertical Complex Wavy Surface

Subject Areas : Mechanical Engineering

Morteza  Ghadimi ¹ (Young Researchers and Elites Club, Science and Research Branch, Islamic Azad University, Tehran, Iran)
Amir  Lotfi ² (Department of Mechanical Engineering, K.N.Toosi University of Technology, Tehran, Iran)
Cyrus  Aghanajafi ³ (Department of Mechanical Engineering, K.N.Toosi University of Technology, Tehran, Iran)

Received: 2017-10-24 Accepted : 2017-12-13 Published : 2018-02-18

Keywords: Mass transfer, Wavy surface, heat transfer, Natural convection,

Abstract :

A numerical study of transient natural convection heat and mass transfer along a vertical complex wavy surface has been performed. A complex wavy surface was created from two sinusoidal functions, a fundamental wave and its first harmonic. The complex wavy surface is maintained at uniform wall temperature and constant wall concentration. An implicit finite-difference scheme is used for analysis. The numerical results demonstrate that the additional harmonic substantially alters the flow field, temperature and concentration distribution near the surface. Also the numerical results show that the local heat and mass transfer rate for a complex surface are smaller than of a flat plate. This decreased local heat and mass transfer rate seems to depend on the ratio of amplitude surface.

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