The Fire Detector And System Of Optic Fiber Bragg Grating In Highway Tunnel

The highway tunnel is a very important traffic hinge. Fire disaster in highway tunnel may result in serious damage to life and property. The highway tunnel should be fitted with fire detectors system for reduce the expenses. The fire detector is used for give an fire alarm to the workers, and at the same time to start up the fire establishments. But at present the fire detectors of the tunnel has much disadvantage, it couldn't be worked well in the highway tunnel. This paper aims at this problem, design a fire detector and its' system for the tunnel, the fire detector is made by the optic fiber grating and memory alloy.In this paper we simply introduced the fire detectors' history, actuality and development. Introduce the highway tunnel's fire characteristic. Compare with kinds of fire detectors, and then choose fire detector for highway tunnel. Through the compare, we can elicit a conclusion that is: the distribute optic fiber fire sensor is better than others, can be used in the highway tunnel. But it also has some disadvantages. The fire detector which based on the optic fiber grating detector technology is better than distribute optic fiber fire sensor. So the optic fiber bragg grating detector can instead of the distribute optic fiber fire sensor in the highway tunnel.Optic fiber bragg grating is a kind of component which is sensitivity with temperature. The detector which make up by optic fiber bragg grating can be used to detect the fire. But in the tunnel, temperature is always fluctuate, and this phenomena can disturb the fire detector's detective. For this, the paper designed a fire detector with optic fiber bragg grating and memory alloy, by using the sensitivity with temperature of memory alloy. In this way the detector can cause another wavelength which is differ from the detector only made by optic fiber bragg grating. So the detector made by optic fiber bragg grating and memory alloy can enhance the veracity in fire alarm.Through the experiments, the paper find when the temperature is above the memory...