Testing Jet Fans in Metal/Nonmetal Mines with Large Cross-Sectional Airways

摘要

The objective of this work was to define jet fan performance in a variety of cross section underground mine applications and to develop guidelines for this performance in open airways, dead headings, and multiple-face areas. Measurements include common ventilation instruments, continuous recording remote electronic anemometers to measure air velocity, and sulfur hexafluoride tracer gas with chromatograph analysis to determine dilution rates and air recirculation. It was determined that: For open airways, large jet fans are less efficient in smaller airways, but effective in larger open airways to achieve both uniformity and greater air entrainment when inclined about 10 degrees or elevated. For dead headings, the jet fan must be placed against the rib of the heading closest to the incoming airstream from the crosscut or recirculation will increase. Larger fans promote recirculation; inclining fans about 12 degrees improves airflow in large heads. In face areas with panels having uncontrolled airflow, the fan should be placed in the incoming airflow, about one pillar in and directed diagonally across the faces. For panels with narrower rooms and controlled airflow, the fan should be placed alongside the panel side in the first room to direct or intersect the incoming airflow at the next entry or crosscut.