A new apparatus using the transient single hot-wire method was developed to measure the thermal conductivity under high pressure.The experimental system was tested by measuring the thermal conductivity of toluene from 286 K to 350 K

with an absolute average deviation from the recommended values of 0.48%.Measurements were performed with liquid dimethyl carbonate over the temperature range from 290 K to 390 K and pressure range from 0.1 MPa to 30 MPa.The data of thermal conductivity were correlated as a function of temperature and pressure.The maximum deviation and the absolute average deviation between the experiment values and the calculated values were -1.97% and 0.86%

respectively.