STUDY OF NON-EQUILIBRIUM PROPERTIES OF NATURAL GASES

It is known that the natural gas under certain conditions such as the presence of fluid inclusions, can exhibit non-equilibrium properties. Non-equilibrium refers to the property of a system to respond to the changes of external environment with some delay. In this case, the typical situation where a non-equilibrium system is in a state of slow change, although external conditions remain unchanged. Non-equilibrium properties are particularly pronounced in technological situations where there is an instantaneous jump in pressure change (start or stop of gas pumping units). To estimate the non-equilibrium properties of gases, usually both identification models, and thermodynamic approach are used. Using of these methods to describe non-equilibrium phenomena in natural gas was chosen as an adequate equation of state. On the basis of this choice the dynamics of changes in the density of the gas at an in-stantaneous change of pressure mode was investigated until the operating mode reaches steady state. The results of the study showed that the stochastic nature of transients in gas pipelines is consistent with the change in the fractal measures of the curves of the dynamics of changes in basic parameters of the flow. The manifestation of non-equilibrium properties of natural gas must be considered during technological calculations in the system for collecting and transporting well products. Bibl. 14, Fig. 3, Tab. 1.