Experimental Study on the Response Characteristics of Photoelectric Smoke Detectors Below Grid Ceilings of Different Hollowing Rate

There are many differences on the setting requirements of fire detectors in the buildings used grid or flat ceilings. In this paper, applied researches on the setting standard of fire detector below grid ceilings were firstly carried out. On the basis of the setting requirements of fire detector, the numerical simulation of smoke movement below and above grid ceilings with four kinds of hollowing rates was conducted in the standard combustion lab by using FDS software. After that, according to the GB4715-2005 National Standard's sensitivity requirements of the 75mm¥75 mm size grid ceilings, the experimental researches on the response characteristics of photoelectric smoke detectors, which were above or under the grid ceilings, were carried out under conditions of different obscuration rates and in FDS simulations. Finally, through comparative analysis of the experimental study and numerical simulation results, the correctness of numerical simulations and the feasibility of using FDS to study the smoke spread below and above grid ceilings were validated.