Experimental Analysis of Heat Transfer from Round Jet Impinging to Asymmetric Concave Surface

Document Type : Research Article

Authors

Department of Mechanical Engineering, Semnan University, Semnan, Iran

Abstract

This study is an experimental effort to investigate the heat transfer from the asymmetry concave surface. For this purpose, an asymmetric cylindrical surface with curvature radiuses of 8 and 12 cm has been considered. Constant heat flux of 2000 W/m2 is applied on the concave surface using a silicon rubber heater mat. In the steady-state condition, the temperature distribution of the concave surface is measured with an infrared camera. The asymmetric distribution of Nusselt number is compared with two symmetrical concave surfaces with curvature radiuses of the 8 cm and 12 cm. In this study, the effects of jet Reynolds number and jet to surface distance on Nusselt number distribution are investigated. The study of asymmetric flow and heat transfer in symmetric and asymmetry surfaces have been carried out for three Reynolds numbers of 23000, 35000 and 50000 and three jet-to-plate distance of 2, 4 and 6. Results show that the concave surface with the curvature radius of 8 cm has more values of Nusselt number distributions in comparison to the surface with the curvature radius of 12 cm. The present results confirm that the Nu distribution is asymmetry along the S axis. In the axial direction, symmetry distribution is observed for the Nusselt number. Also, by reducing the distance of jet from the surface the Nusselt number increases across the asymmetric concave surface.

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References

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Amirkabir Journal of Mechanical Engineering
Volume 50, Issue 6
March and April 2019
Pages 1229-1236

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