Numerical analysis of the effect of baffle on heat transfer enhancement nanofluid flow over a backward facing step: A correlation for the average Nusselt number

Document Type : Research Article

Author

Thermo-Fluids Department, Faculty of Mechanical Engineering, University of Guilan, Iran

Abstract

In this paper, the effect of baffle on the flow field and heat transfer enhancement of forced convection of Cu-water nanofluid flow in the laminar regime over a backward facing step is numerically investigated. Finite volume method is used to solve governing equations of flow and temperature. In this study, the influence of baffle geometrical parameters as height, width and number of baffles, as well as the Reynolds number and the volume fraction of nanoparticles on the flow filed and heat transfer are evaluated. Also, to evaluate the simultaneous of the heat transfer enhancement and pressure drop, the performance evaluation index is calculated. It is obvious that by increasing the Reynolds number and decreasing the volume fraction of nanoparticles, the performance evaluation index is increased. The average Nusselt number and the performance evaluation index for the width of baffle 2 are higher than other cases about 7.6% and 15% respectively. The results show that using 2 baffles must be more beneficial than other number of baffles. Finally, a correlation for the average Nusselt number as a function of Reynolds number, volume fraction of nanoparticles, number of baffles, baffle height and baffle width is presented with an average error of 2.88%.

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References

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Amirkabir Journal of Mechanical Engineering
Volume 53, Issue 7
October 2021
Pages 4309-4328

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