Real Gases and Vapors

Real substances can occur in the three phases solid, liquid and gaseous. In particular, tasks with solutions are presented in which the recording of changes of state in the three technically important regions of the liquid region, wet vapor region and gas region is of interest. In the gas region, the states of the real gas are distinguished from those of the ideal gas. To illustrate the properties of pure substances, the p,v diagram, the T,s diagram, the h,s diagram and the lg p,h diagram, among others, are used in tasks. Thermal equations of state of the form F(p,v,T) are used to represent the properties of ideal and real gases as well as liquids. As the simplest of these equations, the van der Waals equation is treated in tasks; its further development is also considered in tasks. The application of the isenthalpic throttle effect in refrigeration and heat pump systems is discussed.