Experimental and Numerical Comparison of Heat and Flow Characteristics of Concave Heat Sink Using Multi Nozzle Impingement Air Jet

Year 2025, Volume: 2 Issue: 2, 62 - 72, 22.01.2026

Rahmi Erdin , Altuğ Karabey

Abstract

The use of impinging jet cooling applications is increasing every day with the aim of controlling heat transfer. For the removal of high heat from large surfaces, impinging jet systems provide benefits in terms of both cost and efficiency. Studies on impinging jets, which have wide applications in the industry, have attracted attention with the increase in the number of research conducted in recent years. This study examines the heat and flow parameters of a concave heat sink multi-nozzle jet impingement heat transfer. For the analysis of concave heat sinks, three different nozzle diameters (D=25,32,40 mm), three different ratios of the nozzle-to-heat sink distance (H/D=6,7,8), and five different jet velocity values ranging from 5-9 ms-1 were used. As a result of the study, experimental and numerical results were compared to examine how nozzle diameter, dimensionless distance, and jet velocity affect heat transfer characteristics. In the steady state conditions, Nusselt numbers were calculated by measuring the average target surface temperature, and changes in the Reynolds number were also determined. The experiments were also simulated numerically using Ansys Fluent software. The most suitable model, k–ε realizable turbulence model, has been used to compare the numerical results with experimental data. Experimental and numerical results were compared using the Nu–Re diagrams. When comparing the numerical and experimental results, it was discovered that the increase in Reynolds number and nozzle diameter was directly proportional to the average Nusselt number. It has been observed that as dimensionless nozzle distance increases, the Nusselt number decreases. It has been concluded that experimental and numerical data are consistent.

Keywords

Concave heat sink , Heat transfer enhancement , Multi-nozzle impingement jet

References

• Arvasi, S., (2022). Optimization of heat receiver design parameters in multi-multiplier jet heat transfer by Taguchi method, Master Thesis, Van Yüzüncü Yıl University, Institute of Naturel and Applied Science, Van, Türkiye.
• Chen, T. Y. & Shu, T. H., (2003). Flow structures and heat-transfer characteristics in fan flow with and without delta-wing vortex generators. Experimental Thermal Fluid Science, 28(4), 273-282. https://doi.org/10.1016/S0894-1777(03)00107-9
• El-Sayed, S. A., Mohamed, M. S., Abdel-latif, A. M. & Abouda, A .E., (2002). Investigation of turbulent heat transfer and fluid flow in longitudinal rectangular-fin arrays of different geometries and shrouded fin array. Experimental Thermal Fluid Science, 26(8), 879-900. https://doi.org/10.1016/S0894-1777(02)00159-0
• Hadipour, A. & Zargarabadi, M. R., (2018). Heat transfer and flow characteristics of impinging jet on a concave surface at small nozzle to surface distances. Applied Thermal Engineering, 138, 534-541. https://doi.org/10.1016/j.applthermaleng.2018.04.086
• Karabey, A., Al-Ani, R. A. A. & Bozdogan, D., (2022). Experimental and numerical investigation of flow and heat transfer characteristics using impinging jet on optimized rectangular finned heat sinks. Heat Transfer Research, 53, 61–77.
• Karabey, A. & Arvasi, S., (2023). Optimization of the design parameters using the Taguchi method in inclined impingement multijet heat transfer with rectangular finned heat sink. Heat Transfer Research, 54, 37–51. DOI: 10.1615/HeatTransRes.2023046672
• Karabey, A. & Yorulmaz, D., (2025). Experimental analysis of heat and flow characteristics on inclined and multiple impingement jet heat transfer using optimized heat sink. Applied Sciences, 15(5), 1-19. https://doi.org/10.3390/app15052657
• Kınay, H., (2018). Investigation of flow and heat transfer characteristics for impinging slot jets confined with inclined plates, Master Thesis, Karadeniz Technical University, Institute of Naturel and Applied Science, Trabzon, Türkiye.
• Kline, S.J.; McClintock, F.A. Describing uncertainties in single-sample experiments, ASME Mechanical Engineering 1953, 75, 3-8.
• Öztekin, E., (2011). Flow and heat transfer in a slot jet impinging on a concave surface, PhD Thesis, Karadeniz Technical University, Institute of Naturel and Applied Science, Trabzon, Türkiye.
• Poitras, G. J., Babineau, A., Roy, G. & Brizzi, L. E., (2017). Aerodynamic and heat transfer analysis of a impinging jet on a concave surface. International Journal of Thermal Sciences, 114, 184-195. https://doi.org/10.1016/j.ijthermalsci.2016.12.019
• Rakhsha, S., Zargarabadi, M. R. & Saedodin, S., (2023). The effect of nozzle geometry on the flow and heat transfer of pulsed impinging jet on the concave surface. International Journal of Thermal Sciences, 184, 107925. https://doi.org/10.1016/j.ijthermalsci.2022.107925
• Rezaei, M., Ahmadabadi, M. N., Tavakoli, M., Joulaei, A. & Ha, M. Y., (2024). Heat transfer enhancement on a concave surface using sweeping impinging jets: comparison of vortex-based and conventional oscillators. Case Studies in Thermal Engineering, 60, 104738. https://doi.org/10.1016/j.csite.2024.104738
• Tahat, M., Kodah, Z. H., Jarrah, B. A. & Probert, S. D., (2000). Heat transfers from pin-fin arrays experiencing forced convection. Applied Energy, 67(4), 419–442. https://doi.org/10.1016/S0306-2619(00)00032-5
• Tahat, M. A., Babus’Haq, R. F. & Probert, S. D., (1994). Forced steady-state convection from pin-fin arrays. Applied Energy, 48(4), 335–351. https://doi.org/10.1016/0306-2619(94)90004-3
• Yang, B., Chang, S., Wu, H., Zhao, Y. & Leng, M., (2017). Experimental and numerical investigation of heat transfer in an array of impingement jets on a concave surface. Applied Thermal Engineering, 127, 473-483. https://doi.org/10.1016/j.applthermaleng.2017.07.190
• Yang, G., Choi, M. & Lee, J.S., (1999). An experimental study of slot jet impingement cooling on concave surface: effects of nozzle configuration and curvature. International Journal of Heat and Mass Transfer, 42(12), 2199-2209. https://doi.org/10.1016/S0017-9310(98)00337-8