Heat Transfer Enhancement in a Microtube with an In-Line Package of Spherical and Inclined Oval-Trench Dimples during Transformer-Oil Pumping

Pleiades Publishing Ltd - Tập 57 - Trang 885-888 - 2020
S. A. Isaev1, A. G. Sudakov1, A. D. Chornyi2, Yu. V. Zhukova2, A. E. Usachov3
1St. Petersburg State University of Civil Aviation, St. Petersburg, Russia
2Luikov Institute for Heat and Mass Transfer, Belarus Academy of Sciences, Minsk, Belarus
3Central Aerohydrodynamic Institute, Moscow, Russia

Tóm tắt

The vortex-induced intensification of the laminar (at Re = 308) flow of transformer oil and heat transfer in a microtube with an in-line package of dimples with a depth of 0.26 of the tube diameter is calculated based on the Navier–Stokes equations and the energy equation. The heat-transfer increased by nearly 20 times for eight inclined oval-trench dimples spaced around the circumference and by 13 times for spherical dimples equal in area in comparison with that for a smooth tube; moreover, the relative hydraulic losses grow by approximately 30 and 60%, respectively.

Tài liệu tham khảo

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