Potential of gear-ring turbulator in three-dimensional heat exchanger tube from second law of thermodynamic viewpoint
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 4 December 2018
Issue publication date: 6 June 2019
Abstract
Purpose
This paper aims to use the second law of thermodynamic to evaluate the potential of gear-ring turbulator in a three-dimensional heat exchanger tube. Accordingly, a numerical simulation is performed to obtain the irreversibilities in a three-dimensional heat exchanger tube equipped with some gear-ring turbulators for turbulence regime.
Design/methodology/approach
A numerical simulation is performed to obtain the irreversibilities in a three-dimensional heat exchanger tube equipped with some gear-ring turbulators for turbulence regime. The analysis is carried out based on shear stress transport (SST) k-ω turbulent model. The influences of different parameters containing tooth number, free-space length ratios and Reynolds number on frictional and thermal irreversibilities and Bejan number are discussed.
Findings
The results indicated that the thermal irreversibility reduces by decreasing the tooth number. For example, the thermal entropy generation decreases about 25.81 per cent by decreasing the tooth number in the range of 24 to 0 at Re = 6,000. Moreover, the frictional entropy generation decreases by increasing the tooth number as the gear with more tooth number causes a lower flow disturbance.
Originality/value
The present study arranged a numerical work to study the potential of a gear-ring turbulator in a heat exchanger tube from first and second laws of thermodynamic viewpoint. The turbulent flow is considered for this problem. The literature review showed that the usage of a gear-ring turbulator in a heat exchanger tube is not investigated from the second law of thermodynamic viewpoint by previous studies. As a result, the influences of different parameters containing tooth number, free-space length ratios and Reynolds number on frictional and thermal irreversibilities and Bejan number are discussed.
Keywords
Acknowledgements
This research was supported by the Office of the Vice Chancellor for Research, Ferdowsi University of Mashhad, under Grant No. 45512.
Citation
Moghaddaszadeh, N., Rashidi, S. and Abolfazli Esfahani, J. (2019), "Potential of gear-ring turbulator in three-dimensional heat exchanger tube from second law of thermodynamic viewpoint", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 29 No. 4, pp. 1526-1543. https://doi.org/10.1108/HFF-05-2018-0250
Publisher
:Emerald Publishing Limited
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