In these cases, the model predicts flow velocities and temperatures to an accuracy within 10% to 20% of experimental measurements, depending on the resolution of the numerical grid. This indicates that passive fire protection system can alter the thermal conditions inside the tunnel in case of fire.Because the model was originally designed to analyze industrial-scale fires, it can be used reliably when the Heat Release Rate (HRR) of the fire is specified and the transport of heat and exhaust products is the principal aim of the simulation. This study shows tunnel protected with calcium silicate board results in higher temperature and heat fluxes compare to non-protected tunnel and tunnel protected with magnesium oxides/Cement based spray. A comparison of road tunnel with and without various passive protections under heavy good vehicle fire is studied by numerical modelling and presented under this study.

There is a need to better analyze this parameter in tunnel fires and to see their interaction with tunnel fire. The passive fire protection systems are usually not considered as affecting heat release rates in tunnel. These parameters includes but not limited to fuel arrangements, tunnel ventilation, tunnel geometry, fixed firefighting system, fire growth rates etc. Later it was noticed that the heat release rate established by burning of vehicle/fuel in a tunnel gets modified by various other parameters. Many references are available from past researchers on heat release rates for different cases, where different type of vehicle/fuel was burned in a road tunnel. The heat release rate is considered a key parameter for design of various tunnel fire protection systems such as firefighting system, ventilation, and other passive protection systems. A road tunnel fire is characterized by various parameters one of the most important parameter is heat release rate (HRR). Various types of passive protection techniques have been investigated for road tunnels.

Radiation on surface pyrosim