ABSTRACT:

            Improving the heat transfer efficiency of machinery is crucial since it can result in savings on energy, materials, and expenses. Rib-roughening on the heated plane is one method of increasing rate of heat transfer. Rib roughened surfaces are utilized in various industrial applications. Rib roughened surface disturbs the laminar sub-layer and increases the turbulence. Because of increase of turbulence and mixing, rate of heat transfer is improved. Pressure loss is also increased due to rib roughness of heated surface. Therefore, a new rib pattern structure and shape are needed to maximize heat transfer performance while minimizing pressure loss. Computational investigation has been performed to find out the optimum configuration of trapezoidal ribs pattern. Four different configurations of trapezoidal ribs patterns are used in this research paper. The Reynolds number range of 12,640 to 52,410 is considered for the analysis. It is found that ratio of rib pitch to height of 13.3 at Reynolds number of 12640 has maximum thermal enhancement factor of 1.268 from the considered rib roughened channels.

 Keywords:Heat transfer enhancement; Rib roughness; Channel; CFD; Friction factor.

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