Correlation for Nusselt Number and Friction Factor for Solar Air Heater Having Absorber Roughened by Chamfered-square Elements
International Journal of Fluid Mechanics & Thermal Sciences
Volume 5, Issue 2, June 2019, Pages: 50-62
Received: Apr. 9, 2019;
Accepted: May 20, 2019;
Published: Jun. 12, 2019
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Man Singh Azad, CSIR-Central Mechanical Engineering Research Institute, Durgapur, India
Apurba Layek, Department of Mechanical Engineering, National Institute of Technology, Durgapur, India
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The idea of introducing artificial roughness on absorber plate to improve the thermal performance of a solar air heater is very common now days. The technique uses the concept of providing artificial roughness by imbedded element in the absorber plate of the heater. Diagonally chamfered cuboids have been used as roughness element in the current study. A numerical study is performed to investigate the enhancement of the thermo-hydraulic performance of the heater for the various affecting parameters such as Relative Roughness Pitch (Transverse and Longitudinal) of 6 to 14, cross section of cuboids from 8 mm to 14 mm and relative roughness height of 0.44 to 0.088. The range of Reynolds number used in this study was 5000 to 22500. During the study a constant heat flux of 1000 W/m2 on the absorber plate was considered. The standard k-ε turbulence model with enhanced wall treatment of the ANSYS FLUENT software has been used for numerical computation and to handle the flow turbulence. The Nusselt number and the average friction factor are determined for different values of relative roughness pitch and cross sectional areas of the roughness element. Using calculated computational data correlations for Nusselt number as well as friction factor have been developed as a function of flow and roughness parameters for solar air heaters. The predicted and computational values of Nusselt number and friction factor show a good agreement.
Solar Air Heater, Artificial Roughness, Computational Fluid Dynamics (CFD), ANSYS FLUENT, Correlations
To cite this article
Man Singh Azad,
Correlation for Nusselt Number and Friction Factor for Solar Air Heater Having Absorber Roughened by Chamfered-square Elements, International Journal of Fluid Mechanics & Thermal Sciences.
Vol. 5, No. 2,
2019, pp. 50-62.
Copyright © 2019 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/
) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Roy A, Hoque E Md. Performance analysis of double pass solar air heater with packed bed porous media in Rajshahi. AIP Conference Proceedings 1851, 020010 (2017); https://doi.org/10.1063/1.4984639
Hachemi A. Thermal performance enhancement of solar air heaters, by a fan-blown absorber plate with rectangular fins. Int. J. Energy Res. 1995; 19: 567-577.
Chabane F, Moummi N, Benramache S. Experimental study of heat transfer and thermal performance with longitudinal fins of solar air heater. J. Adv. Res. 2014; 5: 183-192.
Chabane F, Moummi N, Benramache S, Bensahal D, Belahssen O. Collector efficiency by single pass of solar air heaters with and without using fins. Eng. J. 2012; 17: 43-55.
Ibrahim Z, Ibarahim Z, Yatim B, Ruslan H Md. Thermal efficiency of single-pass solar air collector. AIP Conference Proceedings 1571, 90 (2013); doi: 10.1063/1.4858635.
Kasayapanand N, Kiatsiriroat T, Vorayos N. Enhanced heat transfer in a solar air heater with double-flow configuration by electro hydrodynamic technique. J. Enhanced Heat Transf. 2006; 13: 39-52.
Rajpoot SS, Koli DK. CFD analysis of solar air heater duct with rectangular rib surface. Int. J. Eng. Trends Tech. 2013; 4: 3006-3011.
Dogra S. Effect of artificial roughness on thermal and thermohydraulic efficiency in rectangular duct of a double pass solar air heater by using transverse ribs on the absorber plate. Int. J. Mod. Eng. Res. 2013; 3: 2271-2274.
Kumar TS, Thakur NS, Kumar A, Mittal V. Use of artificial roughness to enhance heat transfer in solar air heaters - a review. J. Energy Southern Africa 2010; 21: 35-51.
Vyas AA, Shringi D. CFD based thermal efficiency analysis of solar air heater with smooth plate and perforated plate. Imp. J. Interdisc. Res. 2017; 3: 415-422.
Tapas V, Sao AK, Sharma P. Computational analysis of an artificial roughened surface of solar air heater. Int. J. Innovative Res. Sci. Eng. Tech. 2015; 4: 12205-12212.
Prasad BN, Saini JS. Effect of artiﬁcial roughness on heat transfer and friction factor in a solar air heater. Solar Energy 1988; 41: 555-560.
Karwa R, Bairwa RD, Jain BP, Karwa N. Experimental study of the effects of rib angle and discretization on heat transfer and friction in an asymmetrically heated rectangular duct. J. Enhanced Heat Transf. 2005; 12: 343–55.
Arjumand Rasool, Adnan Qayoum. Numerical analysis of heat transfer and friction factor in two-pass channels with variable rib shapes. International Journal of Heat and Technology. 36 91) 2018, 40-48. https://doi.org/10.18280/ijht.360106.
ANSYS FLUENT 13.0 Theory Guide, ANSYS Inc., 2010.