Research on the control law of dust in the main ventilation system in excavated tunnels for cleaner production

Abstract

This study was based on computational fluid dynamics (CFD) and field measurement verification. First, we researched and analyzed the main ventilation system, when closed or opened, of a tunnel boring machine (TBM), to demonstrate that the main ventilation system had the ability to control dust. Then, summarized the theory of pressure airflow dust control in an excavated tunnel. Next, the airflow volume (QM) of the main ventilation system was modified based on different excavation lengths and by adjusting the values of QM from 5 m3/s to 40 m3/s. We found that when QM = 25–30 m3/s, the dust could be effectively controlled, the dust in the working area was effectively controlled within 45.5–55.6 m, and the dust concentration was reduced to less than 9.59–10.50 mg/m3. The accuracy of the CFD results was verified through field measurement, which also showed that the dust concentration was effectively reduced. In conclusion, that the main ventilation system functioned to both supply oxygen and control dust, helping to protect the health of tunnel workers.