Numerical Simulation And Experimental Research Of The Rotating Shield Jet Ventilation In Tunneling Working Face

With the improvement of mining mechanization and increasing of mining strength, dustconcentration in heading face is rising dramatically, which not only have been serious threatsto personal safety of the underground staff, but also bring hidden trouble to normalproduction safety. In the situation of inadequacy ventilation at present, how to effectivelycontrol and timely emit dust in heading face, in order to eliminate the hazard of dust inworking face, is still a serious problem but remains to be solved in tunneling ventilation.In order to improve the environment in the mechanized heading face to meet therequirements of production safety, the rotating shield jet ventilation is put forward based onthe related research. The rotating shield jet ventilation is first studied, at home and abroad, asa new ventilation method. The entrainment and strong mixing ability characteristics ofrotating jet are utilized in rotary shield jet ventilation, which play a role in dispelling dust、gasand hazardous substances in tunneling working face, strengthening the dust-control andcapture. For the flow field of rotary jet is very complex, thus the theoretical analysis issuperficial, not thoroughly researched, mainly relied on the experiment method to explore. Itssuccessful research is not only a major breakthrough of ventilation technology and ventilationtheory, but also make a significant impact on basic theory of the rotary shield jet in furtherresearch. In this paper, the rotating shield jet ventilation in mechanized heading face is regardas the research object. Utilize similarity model and numerical simulation method to analyzethe air flow law of the rotary shield jet in mechanized heading face, with the aid of fluidmechanics, jet theory, the similarity theory and related theory.This dissertation includes the following main content:(1) Analyze flow field formation of the rotating shield jet ventilation in the mechanizedheading face in theory and interpret its dust-control mechanism;(2) Establish the field model of the rotating shield jet ventilation, using computationalfluid dynamics fluent software to simulate its impact parameters (injection angle, nozzleswidth b, blowing and suction ratio), and obtain the best effect parameters. At the same time,the flow field characteristic of rotating shield jet ventilation is analyzed.(3) Rely on similarity theory, use shrink than model, set up experiment platform of therotary shield jet ventilation in similarity model. (4) Use the advanced PIV (Particle Image Velocimitry) technology to measure the flowfield migration of the rotating shield ventilation in mechanized heading face, and theexperimental results verify the numerical simulation analysis. That provides certain value forfuture research work.