Thermal conductivity of aqueous BaI2 solutions in the temperature range 293–473 K and the pressure range 0.1–100 MPa

Measurements of the thermal conductivity of aqueous BaI2 solutions were carried out at temperatures from 293 to 473 K and at pressures up to 100 MPa using a parallel-plate apparatus. The concentrations studied were 2.5, 5, 10, 15 and 20 wt.% BaI2. The experimental uncertainty in the determination of the thermal conductivity was not more than ±1.6%. The temperature and pressure were measured with experimental uncertainties of ±10 mK and ±0.05%. The experimental thermal conductivity data were compared with measured and calculated values in the literature. The data obtained have been used to test the prediction and estimation techniques developed by other authors. The effect of temperature, pressure and concentration on the thermal conductivity behavior was studied. The thermal conductivity shows an almost linear dependence on pressure and concentration at all isotherms for each concentration. Along each isobar, the thermal conductivity has a maximum at temperatures between 405 and 417 K. A new correlation, which yields the correct temperature, pressure and concentration behavior, is proposed. The pressure and temperature coefficients of the thermal conductivity have been studied using derived experimental thermal conductivity data.