Experimental studies on the flammability of mixtures of dimethyl ether

•An experimental apparatus for testing explosion limits was developed.•DME/R134a mixture reaches its CFR when the volume ratio of R134a to DME is about 5.•An explosion limit of DME/R1234yf/R134a mixture is 10.7% by volume.•The critical suppressive line of DME/R1234yf/R134a mixture was investigated.

According to the standard of American Society for Testing Materials, an experimental apparatus for testing flammability of flammable refrigerants was developed. Its reliability was validated subsequently. Studies on dimethyl ether have been performed since it's considered as one of the most alternative substitute for R134a. No experimental or theoretical study has been conducted on the flammability of the binary mixture DME/R134a so far. In this paper, the flammability data of the binary mixture DME/R134a with different volume ratios were tested, the corresponding explosion limits and critical flammability ratio were also obtained. The results show that when the volume ratio of the flame retardant R134a to the flammable refrigerant DME is about 5, the binary mixture reaches its critical flammability ratio. R1234yf is a new and promising alternative, its ternary mixture DME/R1234yf/R134a shows promise as a new air-conditioning refrigerant, a explosion limit was tested and the critical suppressive line of the ternary mixture DME/R1234yf/R134a was presented. The flammability data is of great importance in manufacture and application of the new flammable refrigerants.

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