Evaluation of automatic water cannon for fire protection of low-piled storage in high-clearance facilities

摘要

An experimental study is conducted in this work to evaluate the performance of automatic water cannon (AWC) for fire protection of low-piled storage in high-clearance facilities, with emphasis on reducing the water demand. For this purpose, the water cannon is operated in a simulated automatic mode to allow for changing fire response time, fire targeting accuracy, spray pattern, narrow-angle sweeping, flow rate and delivery distance. The water delivery characteristics including stream trajectory and water flux distribution of the water cannon are measured under no-fire conditions. Large-scale fire suppression experiments are conducted under a 20-MW calorimeter to evaluate the protection performance of the water cannon for low-piled storage of ordinary combustibles. The most important for AWC fire control is to deliver a sufficient water flux to the fire zone. To achieve this flux, the spray targeting accuracy and sweeping pattern are critical to the water cannon operation. Compared to standard ceiling-level sprinklers, the water cannon with targeted water delivery can protect a large area with more than 90% water reduction.