Thermophysical properties of dimethyl ether at near- and supercritical pressures using generalized cubic EoS

• The efficient approach has been proposed to calculate the thermophysical properties of DME at supercritical pressures.
• The RK-PR EoS has shown the reasonably high accuracy over a wide range of thermodynamic states.
• The transport properties such as viscosity and thermal conductivity are well agreed with experimental data.
• This procedure has the potential advantage to treat the DME blending fuels over the existing two-parameter cubic EoS.

The present work has devised the approach for efficiently estimating the thermophysical properties of dimethyl ether (DME) at high pressure conditions relevant to its potential application for compression ignition engines. From a practical standpoint, the thermodynamic properties such as density, heat capacity, enthalpy, entropy, and speed of sound are formulated based on a generalized cubic equation of state (EoS). Comparisons with reference data from a highly accurate empirical multi-parameter EoS demonstrate that the present thermodynamic model has reasonable accuracy for engineering purpose over a wide range of pressure and temperature. By combining it with a transport model which extends the kinetic gas theory with dense-fluid correction, the viscosity and thermal conductivity of DME are also reproduced well for the thermodynamic states from compressed liquid to supercritical fluid.

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