A Comparative Investigation on the Oxidative Combustion of R-1132(e)/R-1216 and R-1132(e)/R-1234yf Blends: A Combined ReaxFF and DFT Study

R-1132(E) (trans-1,2-difluoroethylene) is a low-GWP candidate fully complying with global climate regulations, yet its flammability poses potential combustion risks. This study combined ReaxFF molecular dynamics with DFT to investigate the thermal decomposition mechanisms of R-1132(E) and its blends with R-1216 (hexafluoropropylene) and R-1234yf (2,3,3,3-tetrafluoropropene). Results indicated that initial decomposition occurs through distinct bond-cleavage pathways: perfluorinated R-1216 favors C–C scission, generating CF3 radicals, while hydrogen-containing R-1234yf produces abundant H radicals promoting complete oxidation. The hydrogen‑to‑fluorine ratio dictates product selectivity: increasing R-1216 significantly elevates COF2 yields while reducing HF, whereas R-1234yf maintains stable HF and CO/CO2 outputs. Water accelerates decomposition by scavenging fluorinated radicals and enhancing HF formation. This study establishes reaction mechanisms and quantitative species evolution, providing valuable guidance for the safety assessment of fluorinated working fluids.