Characteristics of natural convective heat transfer in a vertical minichannel with two grooves
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The heat transfer characteristics were investigated in a vertical minichannel with two grooves. The wall geometry of the minichannel possessed grooves with several modified groove ratios. To determine the effects of natural convective heat transfer, the finite volume numerical method was used. The results showed that when d/D = 0.1 and d/D = 0.25, there was no flow separation. When d/D = 0.4, however, there was flow separations at both walls. For the left wall, the local Nusselt number decreased dramatically starting at the leading edge. For the case of two grooves, there were four flow separations at d/D = 0.5. The heat transfer patterns were similar to the single-groove case. However, at the end-section of the first groove, the temperatures dispersed downstream. These heat transfer characteristics corresponded to the flow field. When there was a 1-mm distance between the grooves, the Nusselt number showed a larger variation compared to the other cases. When the channel pitch was 3 mm, the distance between the grooves was not a large factor after a 2-mm groove distance was reached.
Abstract
The heat transfer characteristics were investigated in a vertical minichannel with two grooves. The wall geometry of the minichannel possessed grooves with several modified groove ratios. To determine the effects of natural convective heat transfer, the finite volume numerical method was used. The results showed that when d/D = 0.1 and d/D = 0.25, there was no flow separation. When d/D = 0.4, however, there was flow separations at both walls. For the left wall, the local Nusselt number decreased dramatically starting at the leading edge. For the case of two grooves, there were four flow separations at d/D = 0.5. The heat transfer patterns were similar to the single-groove case. However, at the end-section of the first groove, the temperatures dispersed downstream. These heat transfer characteristics corresponded to the flow field. When there was a 1-mm distance between the grooves, the Nusselt number showed a larger variation compared to the other cases. When the channel pitch was 3 mm, the distance between the grooves was not a large factor after a 2-mm groove distance was reached.
참고문헌 (10)
- M. Ghobadi, "Heat transfer and pressure drop in mini channel heat sinks", Heat Transfer Engineering, 36(10), pp.902~911 (2015)
- J. Hejcik, "Single phase heat transfer in minichannels", EPJ Web of Conferences, 67, pp.1~4 (2014)
- S. E. Ghasemi, "Thermal and hydrodynamic characteristics of water-based suspensions of Al2O3 nanoparticles in a novel minichannel heat sink", Journal of Molecular Liquids, 230, pp.550~556 (2017)
- T. E. Corder, "Computational optimization of a groove-enhanced minichannel", Heat Transfer Engineering, 32(10), pp.876~890 (2011)
- A. Ijam, "Cooling of minichannel heat sink using nanofluids", International Communication in Heat and Mass Transfer, 39(8), pp.1188~1194 (2012)
- 김은필, "Numerical analysis of a channel flow with two tubes in a vertical plain-fin type heat exchanger", 한국마린엔지니어링학회지, 41(5), pp.383~388 (2017), 한국마린엔지니어링학회[DOI]
- 김은필, "Natural convection characteristics in a vertical open channel with partially heated surfaces", 한국마린엔지니어링학회지, 42(8), pp.635~640 (2018), 한국마린엔지니어링학회[DOI]
- S. W. Churchill, "Correlating equations for lamina and turbulent free convection from horizontal cylinder", International Journal of Heat and Mass Transfer, 18(9), pp.1049~1053 (1975)
- F. J. Bayley, "An analysis of turbulent free-convection heat transfer", Proceedings of the Institution of Mechanical Engineers, 169(1), pp.361~370 (1955)