Effects of ejector geometries on performance of ejector-expansion R410A air conditioner considering cooling seasonal performance factor

•The performance of an ejector-expansion R410A air conditioner is measured.•The effect of ejector geometries on the COP and CSPF is analyzed.•The mixing-section diameter of the ejector is optimized based on the CSPF.•The mixing-section diameter is optimized based on the climatic conditions.