The effect of a baffle on the heat transfer in underground auxiliary ventilation systems

Abstract

This paper presents a computational fluid dynamics simulation to examine the effects of the baffle on the air flow field and the heat transfer rate in a space located beneath a ventilation channel. The computational model consists of a two-dimensional channel equipped with a thin baffle hanging from the top wall and a cavity located underneath simulating the underground space. Air flows trough the channel at a uniform velocity, c u , and temperature, c T . The cavity base is assumed to be heated at a constant temperature, h T , while the vertical walls of the cavity are well-insulated. The top wall of the channel is maintained at a constant temperature, c T . The continuity, momentum and energy equations are solved numerically using the control-volume approach to examine a combination of natural and forced convection flows. The results show that even though the existence of the baffle improves the cavity ventilation performance at low Richardson numbers, it has a negative impact at high Richardson numbers.

Optimization of Parameters to Improve Ventilationin Underground Mine Working using CFD

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