Research Article

Numerical Simulation of Effects of Velocity and Diffusion Coefficient on Concentration of Contaminants in the Fluid Flow

K. Langat
Kaplong Boys High School, Kenya
* Corresponding author
J. Shichikha
University of Eldoret, Kenya
J. Bitok
DOI icon 10.24018/ejeng.2022.7.2.2712

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Submitted 2022-01-03
Published 2022-03-15

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Article Main Content

The study developed and implemented Implicit and explicit schemes for solving convection –diffusion equation in one dimension on concentration of contaminant in a fluid flow. The stability of the scheme was analyzed and the accuracy of the solution of the contaminant transport equation was validated by exact available solution. Graphical presentation of the solution for varying velocity and diffusion coefficient was given. The explicit method (EM) involved one unknown on lift hand side (LHS) while implicit method (IM) involved several unknowns on LHS. The study analyzed the effect of velocity and diffusion coefficient on concentration of contaminant in a fluid flow. The developed schemes were solved numerically using MATLAB was to generate the result and in analysis of results. Results showed that concentration of contaminants increased inversely with velocity and directly to diffusion coefficient. Therefore, for proper treatment of water for example, it is necessary to reduce the flow velocities to reduce the trend of contaminants. As Velocity increases the concentration of contaminant decreases and as diffusion coefficient increases the concentration of contaminant increases.

Keywords: diffusion coefficient, explicit method, implicit backward method, velocity

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