RAYLEIGH – BENARD CONVECTION IN EXHAUST SHAFT OVER ONE ROW HORIZONTAL BUNDLE OF FINNED PIPES

UDC 536.24:66.045

  • Karlovich Tatyana Borisovna – PhD (Physics and Mathematics), Assistant Professor, the Department of Energy-Saving, Hydraulics and Heat Engineering. Belarusian State Technological University (13a, Sverdlova str., 220006, Minsk, Republic of Belarus). E-mail: tbkar@mail.ru

  • Sukhotskii Albert Borisovich – PhD (Technical Sciences), Assistant Professor, the Department of Energy-Saving, Hydraulics and Heat Engineering. Belarusian State Technological University (13a, Sverdlova str., 220006, Minsk, Republic of Belarus). E-mail: alk2905@mail.ru

  • Danilchik Ekaterina Sergeevna – PhD student, the Department of Energy-Saving, Hydraulics and Heat Engineering. Belarusian State Technological University (13a, Sverdlova str., 220006, Minsk, Republic of Belarus). E-mail: katya.156.156@gmail.com

DOI: https://doi.org/10.52065/2520-6141-2021-248-2-58-64

Key words: free convection, exhaust shaft, finned tube, heat transfer, Oberbek – Boussinesq approximation, Navier – Stokes equation, Rayleigh – Benard cell.

For citation: Karlovich T. B., Sukhotskii A. B., Danilchik E. S. Rayleigh – Benard convection in exhaust shaft over one row horizontal bundle of finned pipes. Proceedings of BSTU, issue 3, Physics and Mathematics. Informatics, 2021, no. 1 (248), pp. 58–64 (In Russian). DOI: https://doi.org/10.52065/2520-6141-2021-248-2-58-64.

Abstract

The unsteady phenomenon of the appearance of convection flows with a certain periodicity in an exhaust shaft above a one-row horizontal bundle of finned tubes is considered. This phenomenon is interpreted on the basis of solving the thermal and hydrodynamic problems for turbulent fluid flows in the Oberbek – Boussinesq approximation. In the case of lower heating of the air in the shaft by a tube bundle, it is possible to obtain an analytical solution of the Navier – Stokes equation in the form of periodic structures called Rayleigh – Benard cells. Three-dimensional quasiperiodic structures are experimentally investigated using a frame with thin filaments installed in the shaft. It is shown that the number of these structures can be estimated using the Rayleigh number. It has been experimentally demonstrated that convective cells arise above the beam at a height equal to half the height of the shaft.

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14.09.2021