1. The Superheating Process: Superheating typically occurs in a component called a "superheater," which is essentially a heat exchanger located in the path of hot flue gases in a boiler.
• As the steam flows through the tubes of the superheater, it is open to the rest of the steam system.
• Because the steam is free to expand as it heats up, the
Pressure remains constant during the entire process.
2. Benefits of Superheating at Constant Pressure:
• Higher Efficiency: It increases the mean temperature of heat addition, improving the thermal efficiency of the Rankine cycle.
• Prevents Condensation: Superheated steam is "dry." This ensures that no water droplets form inside the steam turbine, protecting the turbine blades from erosion and damage.
• Greater Work Output: It increases the enthalpy of the steam, providing more energy to be converted into mechanical work.
3. Thermodynamic Definition: On a T-s (Temperature-Entropy) or h-s (Mollier) diagram, the superheating process is represented by a curve that follows a constant pressure line (isobar) moving from the saturated vapor curve into the superheated region.