Blasting construction in tunnels always induces
overstandard dust concentration and difficulty in dust removal. Therefore, in
this study, a new threesection spray system is designed,
and its relevant parameters are studied. Based on a selfbuilt spray dust experimental platform, the particle size
characteristics and nozzle applicability of the dust samples at the tunnel
blasting site are analyzed. Moreover, a computational fluid dynamics software
is used to simulate different nozzle layout schemes and incident angles, and
the variation laws of concentration, velocity, and particle size in the droplet
field are analyzed. Furthermore, the dust removal performance of the new spray
system is tested through a field application. The obtained results are as
follows: (1) The peak volume frequency of dust along the tunnel moves toward
the direction of particle size reduction, and the peak volume frequency
increases continuously. (2) The wideangle solid
conical nozzle with a 1.9 mm diameter has better dust suppression effect on the
dust near the face, and the fine solid conical nozzle with a 1.2 mm diameter
has better dust suppression effect on small particle size dust. (3) As the
incident angle increase, the area with dust concentrations exceeding 1 g/m3 in the direct incident area of droplets first increases and then
decreases. (4) When the nozzle is placed at the top, side, and bottom, the
optimal incident angles are 60°, 60°, and 45°, respectively. The field
application shows that the dust removal rates of respiration dust and all dusts
at each measuring point all exceed 75%. Compared with the original dust control
measures, the average dust removal rate of the threesection
spray system is increased by 42.71% and can effectively improve the working
environment of the construction personnel in the tunnel and prevent outward
diffusion of dust in the tunnel.
LIU Ning
,
CHEN Kun
,
MA Wenrong
,
SU Jie
. Novel ThreeSection Spray System and Its
Dustproof Performance[J]. Tunnel Construction, 2022
, 42(4)
: 630
-639
.
DOI: 10.3973/j.issn.2096-4498.2022.04.011
