Study on the Influence of Burner Size on the Maximum Temperature Rise of Smoke Flow Induced by Double Tunnel Fires

Based on FDS, numerical simulations were carried out to investigate the maximum temperature rise of smoke flow induced by double fires in a tunnel with natural ventilation. A full-scale model tunnel was established. The influence of 4 different sizes of double fire sources on the maximum temperature rise under the ceiling is studied when the distance between fire sources is 0 ~ 2 m. Results found that the maximum temperature rise decreases with the increase in burner separation distance and also decreases with the increasing burner size. Based on the model for the highest temperature for the ceiling-jet of one fire source, a new expression considering the burner size and the burner distance was put forward to predict the maximum temperature rise for double fire sources in tunnel fire, which can well correlate the numerical results.