High-Pressure Thermophysical Properties of Eight Paraffinic, Naphthenic, Polyalphaolefin and Ester Base Oils

In this work, the thermophysical properties of four mineral (paraffinic and naphthenic) synthetic (polyalphaolefin ester) base oils are measured. Knowledge these is vital importance for correct optimal formulation design lubricants, development equations state transport models that adequately represent their properties. Density, isothermal compressibility, thermal expansion coefficient, dynamic viscosity, pressure–viscosity contact angle were determined. To carry out a pρT apparatus, rotational viscometer, falling body analyzer used. Highest densities found polyalphaolefin ester oils, increasing around 5% from 0.1 to 100 MPa all oils. The density less dependent on temperature changes. For expansivity compressibility decreases with pressure up 35% 45% observed. From measurements, it was observed higher viscosity grade have worse wetting. greatest effect obtained naphthenic oil lowest oil. Paraffinic present highest universal coefficients.