Impact of Fine Water Mist Curtains on Fire Safety in Historic Buildings: A Case Study of Foshan Historical and Cultural District, Guangdong Province, China

Abstract

ABSTRACT To address inadequate fire separation distances in historical buildings leading to extensive fire spread, practical research employing Fire Dynamics Simulator (FDS) was conducted. The study involved simulating a historical and cultural block in Foshan City to analyze variations in heat flux density and temperatures within a 5-meter radius of windows under fire powers of 1.5 MW, 6 MW, and 10 MW, with window openings at 10%, 25%, and 50%, respectively. The aim was to preserve the original architectural integrity without modifying existing fire separations. Augmentation of fire protection through the implementation of a fine water mist water curtain between buildings was proposed, and its efficacy in smoke and heat insulation was evaluated. Results indicate that, at 1.5 MW fire power, adjacent structures remain relatively secure with current fire separations. However, at 6 MW and 10 MW, fire spread to neighboring buildings was significant regardless of window opening area. Implementation of the water curtain with a nozzle flow coefficient (K) of 80, typical for standard coverage area sprinkler nozzles, and a spacing of 0.8 m, proved effective in enhancing smoke and heat insulation while also offering cost efficiencies. Optimal results were achieved with an average droplet size of 200 µm and nozzle pressure set at 6.0 MPa, corresponding to a nozzle flow rate of 615 L/min. These findings provide valuable insights for drafting specifications for the adaptive reuse of historical buildings and deploying fine water mist water curtains in confined spaces.