Abstract: Abstract: The early (smoldering and initial) fire detection experiments of cable interlayer are carried out through the full-scale cable interlayer experimental platform. The temperature field and CO gas propagation characteristics are studied. Based on the combination of experimental research and numerical simulation, the effectiveness of point-type temperature detector, point-type smoke detector, cable-type temperature detector, and suction-type smoke detector with different response time thresholds is analyzed. The results show that: The temperature field attenuation of smoldering and initial fire presents an exponential function. The average velocity of CO gas propagation in smoldering fire is basically the same when the distance from the fire source increases, but decreases with the increase of the distance from the fire source in the initial fire. The alarm time of cable-type temperature detector is 69% earlier than that of suction-type smoke detector, and 82% earlier than that of point-type smoke detector. Compared with smoldering fire, the initial fire response time of each detector is 56% earlier on average. Under the condition of smoldering fire, the point-type temperature detector fails to report. The response time of fire detector with high alarm threshold is 10% ~ 20% later than that of low threshold detector.

Key words: Key words: power plant, cable interlayer, early fire, temperature field, CO volume fraction, fire detection, response time threshold