Heat Capacity Ratio In Liquids At High Pressure

The heat capacity ratio or Laplace coefficient gamma = C-p/C-V is determined at high pressure and high temperature by a numerical procedure from sound velocity measurements for a dozen liquids, including alkali metals and iron. The obtained data provide insight into this quantity that is difficult to measure experimentally. In addition, an analytical expression of the heat capacity ratio as a function of pressure is proposed, based on reasonable assumptions. This expression can be used for interpolation, extrapolation at high pressure, or to easily convert isothermal quantities into adiabatic ones or inversely. Published under an exclusive license by AIP Publishing.