摘要：In steam power plant, the working medium used for energy transformation is water vapor. The generation process of water vapor has experienced three stages: pre-heat, vaporization and superheat stage. There are five states in the process. They are sub-cooled liquid, saturated water, saturated liquid-vapour mixture, saturated vapor and superheated vapor. The thermodynamic properties of each state are usually obtained by using water vapor tables and charts. The constant pressure process of water vapor is very common in engineering application. In general, we first determine the state parameters by using charts and tables, and then make relevant calculations according to the first law of thermodynamics.
