Foaming Capability, Structural Stability, and Fire Extinguishing Performance Optimization of Short-Chain Fluorocarbon Foam by Modulating Gas–Liquid Ratio

Petrochemical fires pose severe threats to public safety and environmental sustainability, necessitating urgent advancements in efficient and eco-friendly fire suppression technologies. This study systematically investigated the influence of gas–liquid ratio (GLR) on the foam properties and fire suppression efficacy of a novel short-chain fluorocarbon (PFH-BZ) foam fire extinguishing agent. Through comprehensive experimental analysis, the underlying mechanism governing foam performance was elucidated, and the burn-back resistance of optimized formulation was evaluated. The results indicate that GLR significantly impacts PFH-BZ foam performance. Foaming capacity and structural stability exhibit a positive correlation with increasing GLR until reaching a plateau. Low GLRs result in insufficient foam formation and thermal stability, while inducing detrimental combustion intensification. Conversely, excessively high GLRs impair foam spreading capacity, hindering rapid extinguishment. The optimal fire extinguishing performance is achieved at a GLR of 12, where PFH-BZ foam attains an excellent balance among drainage characteristics, spreading capacity, and structural stability. This optimized formulation achieves complete extinguishment within 26.16 s and maintains burn-back resistance of 662.37 s while effectively mitigating the vapor explosion phenomenon. These findings provide critical guidance for the application of a PFH-BZ-based foam extinguishing agent and deepen understanding of the influence of system parameters on suppression performance.