Aspect ratio of thermo-hydraulic performance of periodically prescribed semi-circular groove in rectangular channel

Authors

  • Samson A. Aasa
    Department of Mechanical and Mechatronic Engineering, Faculty of Engineering and the Built Environment, Tshwane University of Technology, South Africa
  • Regan K. Dunne
    Department of Mechanical and Mechatronic Engineering, Faculty of Engineering and the Built Environment, Tshwane University of Technology, South Africa
  • Dawood A. Desai
    Department of Mechanical and Mechatronic Engineering, Faculty of Engineering and the Built Environment, Tshwane University of Technology, South Africa

Keywords:

Convective heat enhancement, Artificial technique, Semi-circular groove, Friction factor, Nusselt number

Abstract

A rectangular channel including an angled groove on the end wall was modeled in an air tunnel to assess the augmentation of heat transfer and the friction factor.  The groove exhibited a 45-degree angle relative to the flow direction, with a pitch-to-groove depth ratio of 6.5.  Three distinct aspect ratios, 0.025, 0.03, and 0.05, were evaluated.  The Reynolds number varied from 1000 to 11000, including laminar to turbulent flow regimes.  The pressure reduction and thermal transfer were quantified in the primary flow of the experimental portion.  The 0.05 aspect ratio yielded the highest performance, with optimal values of 22%, 30%, and 48% in the laminar, transition, and turbulent areas, respectively.  The non-dimensional air temperature of the flow at the conclusion of the test portion demonstrated the dispersion of the fluid, signifying uniform turbulence within the channel.  The impacts of various plate factors on enhancing heat transmission were regulated.  This was ascribed to the channel aspect ratio, mild pressure penalties, and the significant thermal increases of the groove endwalls.  It reduced the thickness of the fluid layer at the surface, facilitated prolonged smooth flow over the groove surfaces, and is essential for enhancing the efficiency and sizing of flat plate heat exchangers in applications such as solar panels, fuel cells, electronic components, motor/generator jackets, bearing jackets, and turbine blades.  The findings indicated that angled grooves can be beneficial in several contemporary applications, including turbine blades, solar cells, and processing equipment.

Dimensions

[1] S. A. Solovitz & T. E. Conder, “Flow and thermal investigation of a grooved-enhanced minichannel application”, Journal of Thermal Science and Engineering Applications 2 (2010) 1. https://doi.org/10.1115/1.4002411.

[2] E. H. Ridouane & A. Campo, “Heat transfer enhancement of air flowing across grooved channels: joint effects of channel height and groove depth”, Journal of Heat Transfer 130 (2008) 1. https://doi.org/10.1115/1.2790022.

[3] P. L. Sharma, D. Bais & P. Thakur, “Thermal instability of rotating Jeffrey nanofluids in porous media with variable gravity”, Journal of the Nigerian Society of Physical Sciences 5 (2023) 1366. http://dx.doi.org/10.46481/jnsps.2023.1366.

[4] S. O. Salawu, R. A. Kareem & J. O. Ajilore, “Eyring-Powell MHD nanoliquid and entropy generation in a porous device with thermal radiation and convective cooling”, Journal of the Nigerian Society of Physical Sciences 4 (2022) 924. http://dx.doi.org/10.46481/jnsps.2022.924.

[5] M. Arik & R. S. Bunker, “Electronics packaging cooling: technologies from gas turbine engine cooling”, ASME Journal of Electronic Packaging 128 (2006) 215. https://doi.org/10.1115/1.2229219.

[6] P. J. Pretorius, G. I. Mahmood & J. P. Meyer, “Static pressure characteristics in pin fin channel with cylindrical pins”, ASME Journal of Fluids Engineering 139 (2017) 091104. https://doi.org/10.1115/1.4036671.

[7] G.I. Mahmood, C.J. Simonson & R.W. Besant, “Experimental pressure drop and heat transfer in a rectangular channel with a sinusoidal porous screen”, ASME Journal of Heat Transfer 137 (2015) 042601. https://doi.org/10.1115/1.4029349.

[8] O.A.Oyekanmi, S.Amole, O.Akinrinola, O.Adedokun, A.K.Dauda, A.O.Awodugba, “Reduced graphene oxide as the electron transport layer in perovskite solar cell: Effect on the photovoltaic performance”, Recent Advances in Natural Sciences 2 (2024) 116. https://doi.org/10.61298/rans.2024.2.2.116.

[9] P. M. Ligrani, J. L. Harrison, G. I. Mahmood & M. L. Hill, “Flow structure due to dimple depressions on a channel surface”, Physics of Fluids 13 (2001) 3442. https://doi.org/10.1063/1.1404139.

[10] G. I. Mahmood, M. Z. Sabbagh & P. M. Ligrani, “Heat transfer in a channel with dimples and protrusions on opposite walls”, Journal of Thermophysics and Heat Transfer 15 (2001) 275. https://doi.org/10.2514/2.6623.

[11] K. Bilen Cetin, M. Gul & T. Balta, “The investigation of groove geometry effect on heat transfer for internally grooved duct”, Applied Thermal Engineering 29 (2009) 753. https://doi.org/10.1016/j.applthermaleng.2008.04.008.

[12] P. S. Lee and C. J. Teo, “Heat transfer enhancement in microchannels incorporating slanted grooves”, in Proceedings of the International Conference on Micro/Nanoscale Heat Transfer, vol. 42924, pp. 819–823, 2008. https://doi.org/10.1115/MNHT2008-52374.

[13] Y. Xie, Z. Shen, D. Zhang & J. Lan, “Thermal performance of a water-cooled microchannel heat sink with grooves and obstacles”, Journal of Electronic Packaging 136 (2014) 021001-1. https://doi.org/10.1115/1.4025757.

[14] E. Eiamsa-ard & P. Promvonge, “Thermal characteristics of turbulent rib-grooved channel flow”, International Communications in Heat and Mass Transfer 36 (2009) 705. https://doi.org/10.1016/j.icheatmasstransfer.2009.03.025.

[15] T. E. Conder & S. A. Solovitz, “Computational optimization of a groove-enhanced minichannel”, Heat Transfer Engineering 32 (2011) 876. https://doi.org/10.1080/01457632.2011.548632.

[16] P. M. Ligrani, G. I. Mahmood, J. L. Harrison, C. M. Clayton & D. L. Nelson, “Flow structure and local Nusselt number variation in a channel with dimples and protrusions on opposite walls”, International Journal of Heat and Mass Transfer 44 (2001) 4413. https://doi.org/10.1016/S0017-9310(01)00101-6.

[17] W. M. Kays & M. E. Crawford, Convective heat and mass transfer, 3rd ed., McGraw-Hill Inc., USA, 1993. https://www.amazon.com/Convective-transfer-McGraw-Hill-mechanical-engineering/dp/0070334579/ref=monarch_sidesheet_title.

[18] J. Liu, G. Xie & T. W. Simon, “Turbulent flow and heat transfer enhancement in rectangular channels with novel cylindrical grooves”, International Journal of Heat and Mass Transfer 81 (2015) 563. https://doi.org/10.1016/j.ijheatmasstransfer.2014.10.021.

[19] International Standard, ISO 5167-1980(E). (1980, July 15). Measurement of fluid flow by means of orifice plates, nozzles and venturi tubes inserted in circular cross-section conduits running full [Online]. Available: https://cdn.standards.iteh.ai/samples/11168/579951b09e254752a0b35aca5b78838b/ISO5167-1980.pdf.

[20] R. K. Ravix & R. P. Saini, “Experimental investigation on performance of a double pass artificial roughened solar air heater duct having roughness elements of the combination of discrete multi V-shaped and staggered ribs”, Energy 116 (2016) 507. https://doi.org/10.1016/j.energy.2016.09.138.

[21] R. L. Webb & N. H. Kim, Principles of enhanced heat transfer, 2nd ed., Taylor and Francis, New York, USA, 2005. https://doi.org/10.1201/b12413.

[22] R. K. Shah & A. L. London, Laminar flow forced convection in ducts, Academic Press, New York, 2014. https://www.sciencedirect.com/book/monograph/9780120200511/laminar-flow-forced-convection-in-ducts.

[23] R. J. Moffat, “Describing the uncertainties in experimental results”, Experimental Thermal and Fluid Science 1 (1988) 3. https://doi.org/10.1016/0894-1777(88)90043-X.

[24] T. G. Beckwith, R. D. Marangoni & J. H. Lienhard, Mechanical measurements, sixth ed., Pearson Prentice Hall, New Jersey, 2015, pp. 42–45. https://link.springer.com/book/10.1007/978-3-030-73620-0.

[25] G. I. Mahmood & A. Samson, “Internal groove influenced thermohydraulic performance on an air-channel”, in Proceedings of the ASME Fluids Engineering Division Summer Meeting, vol. 51555, V001T05A002, American Society of Mechanical Engineers, 2018. https://doi.org/10.1115/FEDSM2018-83236.

[26] S. Han & R. J. Goldstein, “Heat/mass transfer analogy for simulated turbine blade”, International Journal of Heat and Mass Transfer 51 (2008) 5209. https://doi.org/10.1016/j.ijheatmasstransfer.2008.04.002.

[27] Y. Liu, J. Cui, W. Li, & N. Zhang, “Effect of surface microstructure on microchannel heat transfer performance”, Journal of Heat Transfer 133 (2011) 1. https://doi.org/10.1115/1.4004594.

[28] P. Bharadwaj, A. D. Khondge & A. W. Date, “Heat transfer and pressure drop in a spirally grooved tube with a twisted tape insert”, International Journal of Heat and Mass Transfer 52 (2009) 1938. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2008.08.038.

[29] S. C. Lau, R. D. McMillin & J. C. Han, “Heat transfer characteristics of turbulent flow in a square channel with angled discrete ribs”, Journal of Turbomachinery, 113 (1991) 367. https://doi.org/10.1115/1.2927885.

[30] K. Saha & S. Acharya, “Heat transfer enhancement using angled grooves as turbulence promoters”, Journal of Turbomachinery 136 (2014) 081004-10. https://doi.org/10.1115/1.4025733.

[31] O. Abouali & N. Baghernezhad, “Numerical investigation of heat transfer enhancement in a microchannel with grooved surfaces”, Journal of Heat Transfer 132 (2010) 1. https://doi.org/10.1115/1.4000862.

[32] R. L. Webb & N. H. Kim, Principles of enhanced heat transfer, second ed., Taylor and Francis, New York, USA, 2004. https://doi.org/10.1201/b12413.

Air temperature slot at the top endwall.

Published

2025-12-22

How to Cite

Aspect ratio of thermo-hydraulic performance of periodically prescribed semi-circular groove in rectangular channel. (2025). African Scientific Reports, 4(3), 205. https://doi.org/10.46481/asr.2025.4.3.205

Issue

Volume 4, Issue 3, December 2025

Section

ENGINEERING SECTION
Copyright & Licensing

Copyright (c) 2025 Samson A. Aasa, Regan K. Dunne, Dawood A. Desai

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Aspect ratio of thermo-hydraulic performance of periodically prescribed semi-circular groove in rectangular channel. (2025). African Scientific Reports, 4(3), 205. https://doi.org/10.46481/asr.2025.4.3.205

Similar Articles

11-20 of 54

You may also start an advanced similarity search for this article.