Cooling techniques such as increasing air supply,
sprinkling water, and using ice blocks are commonly used when tunneling in
areas with a high ground temperature. Because the long-distance
air supply is difficult, a local cooling technology is proposed to effectively
reduce the internal temperature of a tunnel. The local heat is transferred to
the non-construction area through an air-cooled chiller, a surface cooler, and a cooling water circulation
system device. The comparative calculation results show that the local cooling effect
is far higher than that of ice blocks. Furthermore, the heat transfer in the
tunnel is calculated theoretically, and the cooling parameters of the cooling
system are obtained. The test is conducted in a long tunnel in China, with the
test system 60 m away from the tunnel face, and a 20 kW chiller and an 8 kW
surface cooler are used. The test results show the following: (1) the
temperature of the outlet of the surface cooler is 27.9 ℃, which is 8.1 ℃ lower than that of the
inlet one and meets the temperature requirements specified in tunnel
construction; (2) the air supply distance and volume of the air outlet of the
surface cooler are small, resulting from the low residual pressure of the
surface cooler. According to the result of the field test, four optimization
recommendations are made as follows: adding condensate water recovery device,
installing dust removal equipment in the air inlet, optimizing the performance
of system equipment, and improving the integration degree of the system.
YAN Qintai
,
LIU Wei
,
LI Jianbin
,
YAN Haiyan
,
WANG Xuwei
.
Local Cooling Technology of Long Tunnels Based on AirCooled
Chillers
[J]. Tunnel Construction, 2021
, 41(12)
: 2093
-2097
.
DOI: 10.3973/j.issn.2096-4498.2021.12.009
