Abstract
Backlayering characteristics of thermal fume in tunnel fires were examined in this study. The backlayering distance, in which thermal plume propagates upwind, has not been systematically examined. The phenomenon of backlayering is the most important behavior in tunnel fires. In this paper, the characteristics were examined by the model experiment and the three-dimensional simulation. They were done about the various longitudinal air flows and flames. This simulator is investigated by the large-eddy simulation. The following points of interest are clarified. The simulation result and the experiment result were agreed about the backlayering distances. The non-dimensional backlayering distances can be expressed by non-dimensional heat release rate and Froude number Q^<*1/3> / F_r by the straight- line relation. In the inclinations of expression, the simulation and the experimental result are the same.
