As coal and rock are mined, dust is dispersed into the air. This dust, among other contaminants, poses a serious health and safety risk to mineworkers. Very fine dust known as respirable dust can infiltrate the deepest part of the lungs, and long-term exposure to these particles leads to a disease called coal worker’s pneumoconiosis (CWP). Occurrence of this disease declined steadily over the latter half of the 20th century; however, a recent study indicates that CWP has reemerged with an upward trend beginning at the turn of the century. To combat dust exposure, mine operators use a combination of water sprays and dust scrubbers in conjunction with face ventilation. Additionally, the University of Kentucky has developed a device that passively improves air infiltration to the coal face. Researchers use a variety of modeling techniques, including full-scale, reduced-scale, and computer modeling, to understand active-face flow phenomena. A one-twelfth scale model of an active continuous-miner face was constructed to examine airflow patterns under multiple conditions in a controlled environment. Fluid characteristics and boundary conditions have often been assumed in Computational Fluid Dynamics (CFD) models. Using particle-image-velocimetry (PIV), the flow patterns under various conditions can be measured. The results of these scale model experiments can be used to develop scaling laws which help validate numerical modeling and design of more accurate physical models.
This dissertation presents airflow measurements taken within a reduced-scale model at multiple depths of cut by a continuous miner (CM) while utilizing a machine-integrated scrubber (an active device), a passive wing regulator, and a combination of the two. For conditions where the scrubber is on, there are three power settings, 85%, 100%, and 115% of the curtain air quantity. The results of these experiments identify the relationship of the airflow during the cutting phase and help researchers narrow the number of simulations needed as new ventilation controls or schemes are developed. It also provides realistic baseline cases which can be used for further comparisons
