Thermal regime of fire-protective curtaine at high intensive thermal action conditions

Abstract

Today many offices and trade centers, manufacturing buildings have large areas, which include trade zones, warehouses and etc. Fires in these objects may result in huge pecuniary losses and casualties. One of the most effective fire safety equipment is fire-protective curtains. In case of fire proliferation threat curtain falls to cut pathways of fire, smoke and hot gases to other sectors of building. The curtains may be automatically, remote or manually controlled. The aim of this work is to formulate recommendations for designing of fire-protective curtain with thermal resistance, which could provide ability to withstand high-intensity heat impact of fire in stationary regime. This requires to have thermal model of curtain and consider the ways of heat transfer. Thermal model allows to verify materials of curtain, number of layers, emissivity coefficient, geometry and calculate, how different variations of this parameters influence on thermal resistance. We suggested thermal and mathematic models of fire curtain and solved three examples of curtain: one-layer textile curtain, two-layer textile curtain with air interlayer and one-layer textile curtain with coverage of sloughing material. The results of investigation show, that one-layer and two-layer curtains can’t protect from spread of fire, because of low thermal resistance. These examples may be optimized by usage of several layers, which could reduce thermal radiation from flame, because at high temperatures (about 1000 °C) radiation realizes the main part of heat transfer. For example at textile layer about ten thin metallic polished shields with emissivity coefficient 0.1 have to be installed. Third example of fire-protective curtain showes the best thermal resistance among considered models. It provides high insulating and strength characteristics and allows withstanding intensive thermal action conditions for few hours.