REFRIGERANTS OF THE METHANE, ETHANE AND PROPANE SERIES: THERMAL CONDUCTIVITY CALCULATION ALONG THE SATURATION LINE

In this paper, a formula is presented for the calculation of thermal conductivity of liquids along the saturation line. The formula is valid for organic compounds in a wide reduced temperature range (0.30 to 0.95), but is proven to be particularly reliable for refrigerants by testing it on a database of more than 40 refrigerants of the methane, ethane and propane series that includes almost all those reported by ASHRAE in its 2007 revision of standard 34. The test on the indicated refrigerants shows a very satisfying performance: mean and maximum absolute deviations between calculated values and experimental data are generally less than 3% and 8% respectively. The proposed formula is very simple; three characteristic parameters express the thermal conductivity dependence on the reduced temperature: the constant Φ, a multiplying factor A, and an exponent a.