Experimental investigation on Influencing Factors of air curtain systems barrier efficiency for mine refuge chamber

Air curtain systems for mine refuge chambers prevent harmful gases in the tunnel from entering the chambers, but their barrier efficiency is affected by their structural parameters, installation location and air flow angle as well as the size of the chamber door. Previous studies focused on air curtain systems installed on the top of the door frames of the mine rescue capsule, but no studies have investigated air curtain systems installed on two or three sides of the door frames. To improve the barrier efficiency of air curtain systems for refuge chambers, this study conducted an experimental investigation of the effects of the structural parameters, installation location, and air flow angle on the barrier efficiency for a constant size of the door frame. The results demonstrate that air curtain systems with air curtains installed on two sides of the door frame behind the door wall that ejected air parallel to the door frame provided a relatively good barrier effect; an air curtain system that used pipeline air curtains with a nozzle diameter of 1 mm and a nozzle distance of 15 mm exhibited a relatively good barrier effect and a barrier efficiency of 55-60%. In air curtain systems that use air knives, the air knife gap should be 0.1-0.2 mm wide. Under reasonable parameters and installation conditions, there was no significant difference between the barrier effects against CO2 of air curtain systems that use pipeline air curtains and those that use air knives. (C) 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.