Recommended Values of the Viscosity in the Limit of Zero Density for R134a and Six Vapors of Aromatic Hydrocarbons as Well as of the Initial Density Dependence of Viscosity for R134a. Revisited from Experiment Between 297 K and 631 K

Abstract Previously published experimental viscosity data at low density, originally obtained using all-quartz oscillating-disk viscometers for R134a and six vapors of aromatic hydrocarbons in the temperature range between 297 K 631 most, were re-evaluated after an improved re-calibration. The relative combined expanded ( $$k=2$$ k = 2 ) uncertainty are 0.2 % near room increases to 0.3 higher temperatures. as well mesitylene, durene, diphenyl, fluorobenzene, chlorobenzene, p -dichlorobenzene arranged approximately isothermal groups converted into quasi-isothermal a first-order Taylor series temperature. Then, evaluated by means expansion truncated first order obtain zero density initial coefficients, $$\eta ^{(0)}$$ ? ( 0 ) ^{(1)}$$ 1 . For vapors, Rainwater–Friend theory dependence was used derive values. Finally, reliable also values selected reference measured be applied when generating new formulation.