Free convective combustion on vertical surfaces-variable property analysis and experiments

Abstract

This paper treats the problem of free convective combustion of near vertical fuel surfaces in quiescent oxidant atmosphere, both theoretically and experimentally. The theory improves on existing theories in terms of taking into account variable thermodynamic and transport properties. The locally similar solutions obtained numerically are compared with earlier predictions as well as experiments on mass burn rate, flame stand off and other features. While comparison in the case of some fuels seems bettered by the use of variable properties, the not-too good a comparision in other cases is traced to experimental inaccuracies more particularly related to the non-achievement of steady combustion. To remedy this, an experimental apparatus was carefully designed and the results of these experiments show good comparison with theoretical predictions in all cases considered.