## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Modeling and simulation of natural convection flow along a rough surface of sinusoidal nature with variable heat flux: Using Keller box scheme

**ABSTRACT**

In this study, natural convection flow along a vertical wavy surface has been investigated with variable heat flux. The governing equations are transformed into dimensionless partial differential equations by using the non - dimensional variables and then solved numerically by using implicit finite difference scheme known as Keller Box method. The effects of the parameters amplitude of the wavy surface , exponent of the variable heat flux m and Prandtl number Pr on the local skin friction coefficient and local Nusselt number are shown graphically. It is found that for the negative value of exponent of the variable heat flux m the local skin friction coefficient increases and Nusselt number decreases but the opposite behavior is observed for the positive values of m. The comparison of limiting case with the previous study is shown through table and it is found that the solution obtained is in excellent agreement with the previous studies. α

**KEYWORDS**

PAPER SUBMITTED: 2017-09-29

PAPER REVISED: 2018-01-08

PAPER ACCEPTED: 2018-03-06

PUBLISHED ONLINE: 2018-04-28

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