Calculated assessment of effectiveness of class B fire suppression using automatic fire sprinkler systems

Introduction. The problem of timely activation of fire sprinkler systems is highly relevant for effective fire suppression before the critical moment, when calculated values applied to extinguish the fire, become ineffective. A number of works address the problem of effective application of the fire sprinkler system to Class A fires. The application of such methods to Class B fires has not yet been considered. The model simulating a fire in a room with an automatic fire extinguishing system. The response time assessment model, developed by the co-authors for an automatic water-consuming fire sprinkler system, allows to identify the velocity of flame spreading over the surface of an HFL/CL spillage and the temperature rise rate in the ceiling area in the case of a B class fire. A sprinkler is triggered by the bulb bursting caused by the thermal effect produced by the ascending convection flow. A model has been developed to determine the response time of a fire sprinkler system exposed to the effect of a heat flow, caused by the Class B fire, on a heat-sensitive sprinkler bulb. Activation of a fire sprinkler system by the rate-of-rise heat detector. A model, designated for determining the activation time of a rate-of-rise heat detector, was developed. Examples. A number of examples, illustrating the response time of traditional, deluge, and forced launch fire sprinkler systems, are provided in the article. Conclusions. The obtained formula allows to quickly check the applicability of different types of fire sprinkler systems to ensure the effective protection of premises in which class B fires may break out.