Measurement of thermal diffusivity of ethanol from (293 to 564) K and up to 10 MPa in vicinity of the critical point

Ethanol is a common industrial substance and widely applied in technological and scientific applications, of which the thermophysical properties especially near the critical point are scarce. In this work, the thermal diffusivity of ethanol was determined by the dynamic light scattering method in the temperature ranging from (293 to 564) K and along six isobaric lines including 0.1, 2.5, 5, 6.2, 7.5 and 10 MPa. The relative uncertainty of the thermal diffusivity experimental system is estimated to be less than 2.6% for coverage factor of k = 2 with the level of confidence 0.95. The variation of thermal diffusivity with the temperature and pressure was analyzed. In addition, the comparison between the experimental data and the calculated values from thermal conductivity was made, and the absolute average of relative deviation (AARD) between them is 0.96%.