Thermal Diffusivity of Methanol to a Pressure of 5 GPa

Abstract

Thermal diffusivities of methanol have been measured, using transient optical gratings, at 26 °C, up to a pressure of 5 GPa; together with previously reported measurements of thermal effusivities, they are used to estimate values of methanol’s specific heat and thermal conductivity to a pressure of 8 GPa. At lower pressures, the calculated quantities compare favorably with a published equation-of-state and a separate formulation for conductivity. Use of diffusivities in combination with effusivities is of particular interest, as both can be measured with optical techniques applicable to the high-pressure, diamond-anvil cell. Such experiments thus afford an experimental path to the determination of specific heats and thermal conductivities at the high compressions achievable with this experimental tool.