Measurement of thermal diffusivity for carbon dioxide (CO2) at T = 293.15-406.15 K and pressures up to 11 MPa by dynamic light scattering (DLS)

The sharply increasing use of carbon dioxide (CO2) in area of the trans-critical and supercritical technology urgently requires the study of thermophysical properties of CO2 near the critical point where the lack of the accuracy experimental data is very obvious. The thermal diffusivities of CO2 along six isobaric lines (p = 7.0, 7.5, 8.0 9.0 10.0 and 11.0 MPa) and in the temperatures from 293.15 to 406.15 K were measured around the critical point of CO2. The relative combined standard uncertainty in thermal diffusivity is estimated to be less than 0.01 over the whole examined p-T region. Moreover, the comparison between the experimental data and the calculated results from REFPROP 9.1 were made. The absolute average of relative deviation (AARD) between the experimental data and the calculated results is 3.51% in the investigated region of 0.980 < T/TC < 1.013 and 0.949 < p/pC < 1.503.