Surface radiation influence on the regimes of conjugate natural convection in an enclosure with local energy source

S. G. Martyushev, M. A. Sheremet

Research output: Contribution to journalArticle

1 Citation (Scopus)


A numerical analysis of the unsteady regimes of the natural convection and thermal radiation in a square enclosure with heat-conducting walls has been carried out in the presence of a heat source of finite sizes located in the base zone under the conditions of convective exchange with the ambient medium. The mathematical model formulated in the dimensionless variables "stream function - vorticity - temperature" has been implemented numerically by a finite difference method. The influence of the reduced emissivity of internal surfaces of bounding walls on the local characteristics (the streamlines and temperature fields) and on the integral complex (the mean Nusselt number on typical boundaries) has been analyzed in detail for 0 ≤ e{open} < 1, the location of the heat source 0.1 ≤ l/L ≤ 0.4, and its length 0.2 ≤ l hs /L ≤ 0.6 for Ra = 106, Pr = 0.7. The approximation relations have been derived for the mean convective and radiation Nusselt numbers depending on the reduced emissivity of the internal surfaces of bounding walls and the energy source location relative to vertical walls.

Original languageEnglish
Pages (from-to)417-428
Number of pages12
JournalThermophysics and Aeromechanics
Issue number4
Publication statusPublished - 27 Dec 2013



  • Boussinesq approximation
  • conjugate heat transfer
  • diathermal medium
  • natural convection
  • numerical modelling
  • thermal radiation
  • unsteady regime

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Radiation

Cite this