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J. A. Gbadeyan, T. L. Oyekunle and J. U. Abubakar

**keywords:** Chemical reaction, heat, irregular channel, mass transfer, radiation

An analysis of the effects of thermal-radiation and chemical reaction on free convective heat and mass transfer flow through an irregular (wavy) vertical channel (made up of a finitely long wavy wall at one end and a parallel flat wall at the other) with constant volumetric heat absorption/generation is carried out. The Rosseland approximation is used to describe radiative heat transfer in the limit of optically thick fluids. The non-dimensional governing equations which comprises of continuity, momentum, energy and species equations were simplified using perturbation method and hence written in terms of zeroth and first order set of coupled differential equations. The solutions of these sets of coupled differential equations were obtained for velocity, temperature, concentration and pressure drop of the fluid, using Adomian decomposition method. The expressions for the fluid variables and those of some characteristics of heat and mass transfer namely Skin friction, Nusselt number and Sherwood number obtained from fluid variables are evaluated numerically and presented graphically for various parameters involved in the problem. By carrying out comparisons with the available data in the literature, our numerical results were validated and excellent agreements were obtained. It is noticed among others, that an increase in the radiation and chemical reaction parameters leads to a decrease in the fluid velocity across the entire width of the channel. The temperature decreases with an increase in the radiation parameter, while an increase in the temperature is observed with an increase in the chemical reaction parameter.

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