TY - JOUR
T1 - A U-shaped spray device on a front boom-type roadheader for dust suppression in a metro tunnel
AU - Liu, Ning
AU - Wu, Xiong
AU - Deng, E.
AU - Liu, Xinyuan
AU - Wang, Youwu
N1 - Funding Information:
The authors gratefully acknowledge the support from the projects funded by the National Natural Science Foundation of China ( 52168056 ), the Guizhou Province Basic Research Project ( [2020]1Y250 ), Guizhou Province Ordinary Colleges and Universities Youth Science and Technology Talent Growth Project ( [2021]101 ), Guizhou Province Science and Technology Support Plan Project ( [2020]2Y036 ), the Innovation and Technology Commission of the Hong Kong SAR Government (K-BBY1) and the Hong Kong Polytechnic University's Postdoc Matching Fund Scheme (1-W21Q).
Publisher Copyright:
© 2022
PY - 2023/2
Y1 - 2023/2
N2 - The application of the cantilever tunneling method in urban metro tunnel constructions has been gradually promoted. High concentration of dust will be produced near the working face when a boom-type roadheader is used to excavate a small and narrow metro tunnel in hard rock. If not controlled in time, high concentration of dust will escape in the working wells, the air in cities will be polluted and the health of residents will be affected. To maintain the sustainable development of cities, a U-shaped dust suppression device with optimized nozzle arrangement installed at the front end of the boom-type roadheader is proposed in this study. Firstly, the atomization characteristics of four different types of nozzles were analyzed by an indoor model test. The optimum nozzle is determined to be a fine solid conical nozzle with a diameter of 1.6 mm. Then, the dust diffusion law in the core dust producing area under the action of an air compressor is analyzed based on the discrete phase model of computational fluid dynamics; the influence of the parameters of the complete spray device on the performance parameters of the droplet field is discussed in detail based on the Taylor analogy breakup simulation method. The results show that when the spray pressure is 8 MPa and the number of nozzles is 11, the formed droplet field has the best encapsulation and the high concentration droplets account for 77.36%. Finally, the device is applied and verified on site. The test results show that the maximum total dust suppression efficiency in the tunnel reaches 81.48%, the maximum respirable dust suppression efficiency reaches 81.51%, and the dust suppression efficiency at other monitoring points is also above 70.41%.
AB - The application of the cantilever tunneling method in urban metro tunnel constructions has been gradually promoted. High concentration of dust will be produced near the working face when a boom-type roadheader is used to excavate a small and narrow metro tunnel in hard rock. If not controlled in time, high concentration of dust will escape in the working wells, the air in cities will be polluted and the health of residents will be affected. To maintain the sustainable development of cities, a U-shaped dust suppression device with optimized nozzle arrangement installed at the front end of the boom-type roadheader is proposed in this study. Firstly, the atomization characteristics of four different types of nozzles were analyzed by an indoor model test. The optimum nozzle is determined to be a fine solid conical nozzle with a diameter of 1.6 mm. Then, the dust diffusion law in the core dust producing area under the action of an air compressor is analyzed based on the discrete phase model of computational fluid dynamics; the influence of the parameters of the complete spray device on the performance parameters of the droplet field is discussed in detail based on the Taylor analogy breakup simulation method. The results show that when the spray pressure is 8 MPa and the number of nozzles is 11, the formed droplet field has the best encapsulation and the high concentration droplets account for 77.36%. Finally, the device is applied and verified on site. The test results show that the maximum total dust suppression efficiency in the tunnel reaches 81.48%, the maximum respirable dust suppression efficiency reaches 81.51%, and the dust suppression efficiency at other monitoring points is also above 70.41%.
KW - Boom-type roadheader
KW - CFD simulation
KW - Dust pollution
KW - Sustainable city
KW - U-shaped spray device
KW - Urban metro tunnel
UR - http://www.scopus.com/inward/record.url?scp=85144565867&partnerID=8YFLogxK
U2 - 10.1016/j.scs.2022.104369
DO - 10.1016/j.scs.2022.104369
M3 - Journal article
AN - SCOPUS:85144565867
SN - 2210-6707
VL - 89
JO - Sustainable Cities and Society
JF - Sustainable Cities and Society
M1 - 104369
ER -