## THERMAL SCIENCE

International Scientific Journal

### HEAT AND MASS TRANSFER EFFECTS ON NATURAL CONVECTION FLOW ALONG A HORIZONTAL TRIANGULAR WAVY SURFACE

**ABSTRACT**

An analysis is carried out to thoroughly understand the characteristics of heat and mass transfer for the natural convection boundary layer flow along a triangular horizontal wavy surface. Combine buoyancy driven boundary layer equations for the flow are switched into convenient form via co-ordinate transformations. Full non-linear equations are integrated numerically for Pr = 0.051. Interesting results for the uneven surface are found which are expressed in the form of wall shear stress, rate of heat transfer and rate of mass transfer. Solutions are also visualized via streamlines, isotherms, and isolines for concentration. Computational results certify that, shear stress, temperature gradient and concentration gradient enhances as soon as the amplitude of the wavy surface, a, increases, but complex geometry do not allow to carry simulations for a > 1.5. This factor probably ensures that sinusoidal waveform is better than triangular waveform.

**KEYWORDS**

PAPER SUBMITTED: 2015-07-22

PAPER REVISED: 2016-03-22

PAPER ACCEPTED: 2016-04-23

PUBLISHED ONLINE: 2016-05-08

**THERMAL SCIENCE** YEAR

**2017**, VOLUME

**21**, ISSUE

**2**, PAGES [977 - 987]

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