Heat Transfer Enhancement in a Dimpled Narrow Channel during the Transformation of Separated Turbulent Flow with Increasing Slope Angle of a Solitary Conical Dimple

被引：0
作者：
S. A. Isaev
D. V. Nikushchenko
I. A. Popov
A. G. Sudakov
N. V. Tryaskin
L. P. Yunakov
机构：
[1] St. Petersburg State University of Civil Aviation,
[2] St. Petersburg State Marine Technical University,undefined
[3] Tupolev Kazan National Research Technical University,undefined
[4] Baltic State Technical University “Voenmeh” named after D.F. Ustinov,undefined
来源：
High Temperature | 2022年 / 60卷
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摘要：
A numerical study of turbulent (Re = 40 000) flow around a solitary conical dimple with a depth of 0.233 of the spot diameter on the wall of a narrow channel (with a cross section of 2.5 × 0.33) is carried out with change in slope angle θ. The transformation of the jet-vortex structure of the mean flow from a symmetric system of paired vortices to a monotornado flow leads to an intensification of the separated flow and heat transfer enhancement. The maximum velocities of the return and secondary flows increase by 25 and 40%, respectively, while the maximum turbulent energy drops abruptly by 30%. The minimum relative negative friction at the bottom of the dimple decreases by a factor of 2.5 (reaching –1.5). After θ = 45°, there is a fairly rapid decrease in the intensity of the separated flow in the dimple. The thermal efficiency of the control section with a dimple noticeably lags behind the growth of relative hydraulic losses; however, thermal-hydraulic efficiency THE = (Numm/Nummpl)/(ξ/ξpl)1/3 is close to unity.
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页码：208 / 214
页数：6
相关论文
共 54 条
  • [1] Rashidi S.(2019)undefined Appl. Energy 259 1491-undefined
  • [2] Hormozi F.(1983)undefined Soc. Mech. Eng. 26 1744-undefined
  • [3] Sunden B.(2004)undefined Heat Transfer Res. 35 34-undefined
  • [4] Mahian O.(2016)undefined J. Eng. Phys. Theromophys. 89 1195-undefined
  • [5] Hiwada M.(1997)undefined J. Enhanced Heat Transfer 4 131-undefined
  • [6] Kawamura T.(2017)undefined Int. J. Heat Mass Transfer 109 40-undefined
  • [7] Mabuchi I.(2019)undefined Energies 12 1-undefined
  • [8] Kumada M.(2000)undefined Dokl. Ross. Akad. Nauk 373 615-undefined
  • [9] Buanker R.(2003)undefined High Temp. 41 229-undefined
  • [10] Belen’kii M.Ya.(2016)undefined Int. J. Heat Mass Transfer 94 426-undefined
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