Effect of natural convection and radiation inside of a hollow beam in a standard fire

Abstract

In the design of steel structures, special attention must be paid on structural fire design in order to ensure a specified safe time period that the structure can withstand the fire without collapse. In the European design rules, the standard practise assumes uniform temperature for steel beam cross sections while the surrounding area is subjected to the so called standard fire. When the ambient temperature field is not uniform (e.g. at beam joint areas) neither will be the beam cross section temperature field. This paper studies the contribution of natural convection and cavity radiation to the temperature field of a hollow beam cross section in the case of non-uniform ambient temperature by using transient CFD-simulations.<br/>