Verisimilar research on the dust movement in the underground tunneling at the roadheader cutterhead dynamic rotation

Abstract

The fast mechanization excavation brings a sharp rise on the dust concentration in the confined tunneling space. In this paper, a full-scale verisimilar tunneling scenario is constructed in Ansys Fluent platform based on the real cutterhead dynamic rotation. The objective is to investigate the behavior characteristics of dust movement exerted by the rotary cutterhead. The result shows that the rotary cutterhead produces a distinctive additional airflow field, which causes a low-velocity zone in the windward and then massive dust sedimentation. There are dust accumulation zones prevalent in the front cutterhead, hydraulic rod, and exhaust air duct. The vortex area extends dramatically in the central hydraulic rod, and the vortex number declines as the distance lengthen. The rotary cutterhead strengthens the additional airflow that promotes the intersection point a clockwise shift. Raising the rotary speed shrinks the dust concentration volume by 54.5% and 82.7% around the cutterhead and rocker. The additional airflow exerts a dominant role in the resultant wind velocity at a low exhaust velocity. The intersection position migrates anticlockwise with the exhaust velocity rise. Increasing the exhaust velocity has a positive effect in suppressing dust in the cutterhead and the driver position.