ABSTRACT
Blowing curtain systems are preferable by many continuous miner operations as they are considered superior in their removal and dilution of pollutants such as methane gas. However, numerous field tests, laboratory experiments, and numerical models also show a massive separation of airflows and the formation of vortices close to the blind headings. Airflow recirculation prevents fresh air from reaching the active face. Computational fluid dynamics simulations using Reynold’s Averaged Naviers Stokes (RANS) approach have successfully reproduced the observed phenomenon. These steady-state models cannot resolve the transient state eddies observed in the entries of coal mines. Moreover, these are computationally expensive when a high resolution is desired. Reduced scale physical prototypes could be used to mimic the full-scale phenomenon when scaling laws are applied. This paper summarizes the scale modeling of airflows on a reduced scale model. The particle image velocimetry (PIV) technique was used to validate the flow separation from the ribs. Large eddy simulations (LES), as presented here, also resolve those transient-state eddies and the flow separation. Results from PIV tests and LES models set up and run on equipment-free box and slab cuts are presented.
