A new tunnel fire detection and suppression system based on camera image processing and water mist jet fans.

Several tunnel fire detection and fighting systems are currently available in the market, each with its own pros and cons. Although no single system is perfect, the water mist system is one of the top-performing conventional tunnel fire suppression systems available. The problem is that such system is expensive. More affordable equipment with similar performance would be a breakthrough in the field of tunnel safety. Accordingly, this study develop a new water mist system, in which ventilation jet fans are utilized in such a way to achieve economical feasibility. The system features monitoring cameras use to determine fire coordinates and mist-generating jet fans employed to suppress fire. The front of the ventilation jet fans is equipped with nozzles, which spray water frontward through the fans, thereby creating mist and propelling it toward the location of a fire. The mist that shoots out of the fans reduces ambient temperature, flushes oxygen, cools the surface of inflammable materials, and weakens radiative and convective effects. The simulation of the proposed system shows a low heat release rate, smoke and toxic fumes reduction, tunnel ventilation speed increases, and improved visibility. These improvements enhance tunnel safety and make tunnel conditions during a fire less threatening to human health. The cost of the system put forward in this work can be further reduced by optimizing the materials that constitute the pipes and fittings and removing the firefighting pumps.