隧道内的纵向风会改变隧道内的热对流和烟气分布,从而影响感温定位误差。从相关部门对隧道火灾探测的强制验收规定(点火后60 s内必须发出报警信号)出发,开发了一种利用光纤光栅感温火灾的探测技术。通过采集不同风速、不同点火位置条件下多次点火实验的温度场,分析了不同工况下的温度场分布及其动态变化,提出了根据温度场修正着火点报警位置的智能算法。该算法可根据隧道火灾温度场分布和动态变化,修正纵向风带来的火灾报警位置误差,并在规定时间内智能判断火灾发生位置。

The vertical wind in a tunnel will change the heat convection and smoke distribution in the tunnel and influence the temperature-sensing error. This study starts from the relevant state departments for the mandatory acceptance of tunnel fire detection (i.e., the alarm signal must be generated within 60 s after ignition). A fiber grating temperature sensing fire detection technology used to collect the temperature field of multiple ignition experiments under different wind speeds and ignition positions is then developed. The temperature field distribution and its dynamic changes under different working conditions are analyzed. Subsequently, an intelligent algorithm for correcting the fire point position based on the temperature field is proposed. The problem of the position error of the fire alarm caused by the longitudinal wind is corrected according to the temperature distribution and the dynamic change of the tunnel fire. In addition, the fire location can be intelligently determined within the specified time.