Methodology for Measurements of the Properties of Not Fully Stable Fluids

The report is devoted to measurements of the properties of a substance which is in a not fully stable state, i.e., superheated for a short time with respect to the liquid-vapor equilibrium line, liquid-liquid (for mixtures) equilibrium temperature or the onset temperature of thermal decomposition of a substance in a quasi-stationary process. The specificity of probe measurements on the scale of small times and sizes characteristic of such states is discussed. Some results of measurements of the properties of superheated liquids, which are not feasible in the framework of quasi-stationary methods, are presented. The measurements are carried out by two techniques within the framework of the general approach, namely a wire probe (resistance thermometer) technique and an optical probe (fiber-optic waveguide) one.