Abstract: To study the influence of tunnel transverse fire source location on the ceiling temperature distribution along longitudinal process, the method of combining numerical simulation with full-size model experiment is adopted to analyze the ceiling temperature rise generated by the combustion of the three ignition sources at various lateral offset positions and central line ignition sources. The results show that for a variety of transverse offset fire sources, the longitudinal temperature rise attenuation of the fire source can still be described in exponential form, and the closer to the side wall of the tunnel, the faster the temperature rise attenuation is. The coupling effect of the offset distance and longitudinal distance between the ignition source and the transverse center can be described by a relatively independent experienced formula. The larger the power of the ignition source, the smaller the range of the influence of different offset ignition sources on the longitudinal attenuation of temperature rise.

Key words: tunnel fire, offset fire source, ceiling, temperature distribution