Papers by Keyword: Fire Suppression

Abstract: High-rise buildings have some characteristics such as high altitude, complex structure and various functions. Once in fire, casualties and property loss might be more frequent in high-rise buildings. In order to reduce the fire caused casualties and property losses effectively, the characteristics of high-rise buildings were analyzed and concluded in this paper, and related suppression strategies were also put forward. A few suggestions were given to the study of fire suppression in high-rise buildings in the future in according to the research situation.

Abstract: Water mist technology has been developed and regarded as a promising substitute fire-extinguishing agent in spacecraft. In this paper, a numerical simulation method is introduced to investigate the effect of water mist size, velocity and flow rateon the fire suppressionefficiencyin microgravity. The fire extinguishing efficiency is better for the finer water mist in microgravity due to better heat transfer and more rapid vaporization. The evaporation cooling is the dominant mechanism of fire suppression in microgravity.As for the water mist velocity, the performance of fire suppression is affected slightly in microgravity. The results on the effect of water flow rate show that the flow rate should be higher than a critical value to suppress the fire effectively.

Abstract: According to the automatic fire extinguishing equipment requirements for explosion suppression platform system, this paper using the flexible neural tree and the clonal selection principle, describes the creation method of flexible neural tree model, embedded virtual instrument technology, to solve the nonlinear system fault diagnosis problem, realize the fire (explosion) detection system control components, improves the diagnostic sensitivity and accuracy. After the trial, the equipment illustrates high integrity, good versatility and high stability.

Abstract: Fire detection system has been developed for years, but the existing systems are either non-intelligent or non-integrated. This paper supposed a design of an intelligent and integrated fire safety surveillance system. We integrate video fire detection, fire positioning and fire suppression together into one intelligent system. Firstly, the video fire detection subsystem could recognize fire in the monitoring scene by processing the image sequences from the camera in real time. This subsystem will send fire alarm and video of fire scene to the control centre, and the centre will give positioning commands to the fire positioning subsystem. Secondly, the fire positioning subsystem will compute the coordinates of fire by images from two cameras of different position. The position information of fire will be also sent to the control centre and the centre will command fire suppression subsystem to work. Finally, the fire suppression subsystem could adjust the water cannon to the fire according to the coordinates of fire and spray water to put out the fire automatically. This integrated system can work independently and automatically. This system is applicable to various places, such as warehouse, workshop, dormitory, etc.

Abstract: Extinguishing performance of portable water mist system was studied in this paper, considering the effects of additive addition and its type. The experimental results were statistically processed and numerically analysed by mathematical software. The results demonstrated that water mist with additive solution can extinguish pool fire efficiently due to physical and chemical mechanisms. The salt solution produces better fire control result than surfactant solution at low concentration, whereas the surfactant solution brings the better one at high concentration. Furthermore, the salt solution and surfactant solution have similar fire expansion behaviours to pure water in fire suppression with portable water mist system. The study, based on the application of the portable water mist system with additives, revealed that the system performed well on fire suppression and could be useful on movable fire control.

Abstract: Fuel system is the most vulnerable system on fixed wing aircraft. When penetrated by threat propagators, it is liable to be damaged by combustion and explosion. Thus, fire/explosion suppression for fuel system are important measures to improve the aircrafts survivability. In this paper, the whole aircraft vulnerability model which consists of aircraft configuration, structure, and systems is constructed by CATIA software, the basic steps for vulnerability quantitative computation are descried, and the computing formulas of three kill modes are presented. The vulnerability of one aircraft before and after adopting fire/explosion suppression measures are analyzed. The results show that fire/explosion suppression measures can effectively decrease the aircrafts vulnerable area and kill probability.

Abstract: A numerical study on the interaction of water mist with a fire plume was conducted using FLUENT software. The effects of different mist characteristics, such as droplet size and spray intensity, was considered in this simulation. The fire plume temperature history and velocity field were investigated. The results show that with a certain droplet size of water mist, the extinguishing time will be shorter when the mass flow of water increases, but this effect is no longer distinct after the mass flow of water mist increased to a critical value.

Abstract: The experiment on gas jet flame extinguishing with water mist in open space was conducted in this paper. On the basis of experimental result, the process of the flame extinguishment can be classified into two categories:1) when fuel flow rate is small, the gas jet flame can be suppressed and extinguished quickly; 2) When fuel flow is large, the flame lifts from the attached position at the burner exit after suppressed by the water mist. FLUENT is used to simulate the interaction of water mist with gas jet flame. The Eddy-dissipation model (EDM) is used for combustion of flame. the water mist is simulated by Discrete Phase Model (DPM).The simulated results agree well with the experimental results. To some extent, EDM is suitable for simulating the interaction of water mist with a turbulent gas jet flame.