A Modeling Study on Longwall Tailgate Ventilation

A Modeling Study on Longwall Tailgate Ventilation
Jürgen Brune, Colorado School of Mines, Golden, Colorado, USA Michael Sapko, Sapko Consulting Services, Finleyville, Pennsylvania, USA

ABSTRACT: In the United States longwall gobs are usually ventilated with bleeder systems. These bleeders are
designed to dilute, render harmless, and carry away flammable, explosive, noxious, and harmful gases, dusts,
smoke, and fumes from the active mining areas.
One of the most critical areas for longwall ventilation is the tailgate corner. This paper uses computational
fluid dynamics (CFD) simulations using the Fire Dynamics Simulator (FDS) by the National Institute of
Standards and Technology (NIST) to analyze the ventilation and potential methane accumulation and mixing
patterns in the tailgate corner area. Ventilation airflow in the longwall tailgate is essential to proper methane
dilution and helps prevent methane-rich air from being drawn from the gob. Positive ventilation may be
obstructed if the tailgate entry immediately inby the longwall face cannot be kept open due to caving of the roof
and/or floor heaving.
CFD simulation results illustrates the impact of various ventilation patterns and suggest improved ventilation
and ground control practices to reduce the hazardous accumulations of methane in the tailgate areas of longwall
sections. Simulations also suggest re-evaluation of the locations of methane monitoring approaches to detect and
warn of potential methane accumulations in the tailgate before the shearer cuts into the tailgate.Click here for the full document on this interesting topic.