Experimental and simulation study on performance evaluation for flame retardancy of polyurethane

Abstract

Rigid polyurethane (RPU) is widely used as an insulation material for construction; however, it induces the production of toxic gases in the case of a fire. Thus, the development of RPU with enhanced flame retardancy is required. In this study, a series of flame retardancy evaluation methods are presented, ranging from a property-based method to a computational fluid dynamics (CFD) numerical method combined with a pilot-scale experiment (PSE). The reliability of the CFD numerical analysis was assessed using the coefficient of determination (R2), and flame-retardant performance was evaluated by comparing the CFD results with the life safety assessment represented by the available safe escape time (ASET). Case studies based on these methods revealed that the peak heat release rate (PHRR) of the RPU1/IFR sample, which was structurally stable and incorporated an intumescent flame retardant was reduced by 243% compared to RPU0, and the limiting oxygen index (LOI) was 18%. In addition, CFD analysis showed that the ASET of RPU0 was 314 s shorter than that of RPU1/IFR. Based on the results of this study, we propose a new safety management system for fire safety using the comparative results of experiments measuring the flame retardancy of RPU and numerical analysis.