Investigation of characteristics of bounded wall jets in dead end mine headings.
Lexington, KY: University of Kentucky, 2004 Dec; :1-77
A comprehensive experimental study has been conducted using Particle Image Velocimetry (PIV) for a wide array of ventilation schemes and mining configurations for the purpose of examining ventilation characteristics in dead end mine headings. Flow behaviors in two basic mining sequences of box and slab cuts for 30 ft and 60 ft deep cuts were studied. The present thesis discusses the effect for various geometric and flow parameters including the variation of inlet flow velocities, entry heights, face zone widths and curtain widths on the flow behavior. The Reynolds number Re considered for this study ranges from 1 105 to 3 106 based on curtain width and exit velocity. The variation of the face zone and the curtain widths considerably affected the flow behavior, resulting in recirculation regions in the face area for critical combinations. Jet spreading angles and virtual origins have been calculated for the different geometries showing that an optimum range of face and curtain widths exists. A detailed discussion employing various scenarios for exhaust ventilation systems has also been made. Full-size measurements and comparison of the experimental data with numerical simulations is presented. Implementation of machine-mounted scrubbers in the blowing system are discussed for different values of the ventilation ratios (Qs/Qin) ranging from 14% to 53%. The scrubber system, typically introduced for dust collection, is also shown to be a useful tool in providing adequate ventilation to the immediate face area.
Mining industry; Ventilation systems; Mining equipment; Coal mining; Underground mining; Models; Computer models; Simulation methods;
Author Keywords: Mine Ventilation; Flow Separation; Mining Scenarios; Wall Bounded Jets; Scrubber Ventilation System
Research Tools and Approaches: Control Technology and Personal Protective Equipment
Investigation of characteristics of bounded wall jets in dead end mine headings
University of Kentucky