Research on the combustion characteristics of R1243zf and its binary mixtures with R134a and R13I1

Working fluid is the key medium to realize energy conversion in the cycle system. 3,3,3-trifluoropropene (R1243zf) has attracted extensive attention for its excellent thermodynamic properties and environmental protection performance, but its flammability limits its practical application. In this paper, the combustion characteristics of R1243zf and its binary mixtures with R134a and R13I1 were investigated. Firstly, the effect of the equivalence ratio on the combustion characteristics of R1243zf was analyzed. As the equivalence ratio increased, the theoretical equilibrium temperature, explosion pressure, and burning velocity first increased and then decreased, reaching maximum values of 2310 K, 9.01 atm, and 13.8 cm/s at equivalence ratios of around 1.0, respectively. Then, the effect of humidity on the burning velocity of R1243zf was analyzed. As the relative humidity increased, the concentrations of H and OH radicals rose, which in turn led to an increase in the burning velocity of R1243zf. Finally, the effect of flame retardants on the burning velocity of R1243zf was measured. The burning velocity of the mixtures decreased with increasing concentrations of R134a and R13I1. The reaction pathway and inhibition mechanism of flame retardants were revealed. The inhibition effect of R13I1 on combustion reactions was significantly better than that of R134a.