To clarify the key parameters of a heating insulation
system for a highway tunnel fire pipeline that utilizes solar energy, a
numerical calculation model of a "pipe in a pipe" system is
established based on the Fucunchuan tunnel project. This model determines the
insulation layer thickness and inlet temperature that are both economically and
practically reasonable. Furthermore, a heat transfer amplification factor that
comprehensively reflects the heating of the closedloop
pipe is proposed through fitting calculations. The results reveal the
following: (1) There is an upper limit to the effectiveness of the external
insulation layer, and a reasonable thickness of about 50 mm should be
maintained. Additionally, the inlet temperature of the heating pipe should be
kept above 40 ℃ to effectively guarantee the antifreeze
effect of the fire pipeline system. (2) The numerical calculation results of
the second heat transfer process are in good agreement with the theoretical
results, which validates the reliability of the numerical results. (3) Based on
numerical results and considering the first heat transfer process, a heat
transfer calculation formula of doubletube closedloop heating is proposed. The feasibility of this formula is
validated through the Fucunchuan tunnel project, and it is suggested that when
the water temperature of the fire pipeline is below 36.4 ℃, the fire pipeline will not freeze.
GAI Weipeng
,
ZHAO Yawan
,
GAO Xuan
,
SHEN Yabin
,
ZHAO Lijuan
. Heat Transfer Mode and Key Parameters of Fire Pipeline
in Fucunchuan Tunnel[J]. Tunnel Construction, 2023
, 43(2)
: 265
-272
.
DOI: 10.3973/j.issn.2096-4498.2023.02.008
