## THERMAL SCIENCE

International Scientific Journal

## Authors of this Paper

,

### MATHEMATICAL MODELING OF HEAT TRANSFER FROM IMMERSED HEATED SURFACE TO PACKED BED

ABSTRACT
In this paper, the results of the investigation of the steady forced convection in cylindrical porous bed heated electrically by heater placed in bed axis, are presented. The main aim of the investigation was to provide more data on the pressure, velocity and temperature distributions for flow situations characterized by velocities lower than minimum fluidization velocity. The cylindrical porous bed consisting of glass spheres, which is heated radially and symmetrically, has been taken as physical model. The boundary conditions of the second kind (q = const.) have been realized on the surface of heater. By analyzing the forced convection phenomenon, the dominant mechanism for heat and momentum transport, have been observed. This was the basis for establishing the mathematical model. The peculiarity of the mathematical modelling presented in this paper is that the porous bed has been treated as pseudo homogeneous medium (i.e, quasi continuum). According to the above assumption, the basic transport equations have been obtained by using the method of volume averaging. The proposed mathematical model was solved numerically by using the control volume method. In order to perform this numerical procedure, the original computer program has been constructed. The obtained results of the applied prediction method for velocity and temperature distributions give a significant verification of: the noticed transport phenomena and its mathematical modelling, the chosen unambiguity conditions and the validity of the applied numerical procedure.
PAPER SUBMITTED: 1998-06-20
PAPER REVISED: 1998-09-01
PAPER ACCEPTED: 1998-10-11
PUBLISHED ONLINE: 2020-09-20
THERMAL SCIENCE YEAR 1998, VOLUME 2, ISSUE Issue 1, PAGES [71 - 80]
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