Flame extension length and temperature profile in thermal impinging flow of buoyant round jet upon a horizontal plate

摘要

This paper investigates the flame extension length and temperature profile in a thermal impinging flow, induced by a buoyant turbulent round jet impingement upon a horizontal plate, focusing on the scenarios that flame heights are comparable to or larger than plate-source height. Results show that the measured flame extension lengths in this work with a wider range [(H-f-H)/D from 0 to 14.5] can be still well approached by the You and Faeth's correlation obtained from limited data range [(H-f-H)/D from 0 to 5.8]. New correlations to predict the flame extension length are also developed based on physically the unburnt fuel (at impingement) estimation with cylindrical- or ellipse flame shape hypothesis. The change of maximum temperature at the impingement zone along with plate-source height is found to be well described by a three-regime law. A new correlation is proposed, with modified characteristic plume radius, to collapse the horizontal temperature decay profile with H-f/H up to 4.13. (C) 2014 Elsevier Ltd. All rights reserved.