BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI

80 Gelu Coman and Valeriu Damian
mathematical solution to the problem are made difficult by the fact that general
solutions relate to three-dimensional nonstationary temperature fields in bodies
whose physical properties are temperature dependent.
2. Problem Formulation
Numerical modeling was performed using Fluent 6.3 software for two
cases of skating track construction, namely: track with water immersed pipeline
and track with pipes buried in sand. For symmetry purpose the study was
conducted using a flat discretization network, bordered left and right by two
vertical lines passing through the mid distance between two consecutive tubes, a
straight horizontal line representing the water (or ice) surface and another one
that represents the track foundation board (Fig. 1).
With the water submerged pipe geometry , the calculation range is identically
bounded, specifying that the entire area around the pipe was considered of
liquid type .
The grid with the water submerged pipe geometry contains 13563 nodes
and 12952 quadrilateral elements, and in the second case ,with the pipe buried
in the sand, 11243 nodes and 10896 elements.
The Fluent program has an impressive library of solid and fluid materials
and their properties. Numerical modeling of heat transfer with phase change
made with this software, physically corresponds to the real solidification
process around the cylindrical surfaces. Thus, the thermophysical properties of
materials are no longer constant but vary with temperature and the phase
change is not isothermal
Water
surface
Sand
surface
Pipe
surface
Track
foundation
board
surface
Fig.1 – The surfaces of the analyzed domain.