In a steam power system, where is steam superheating carried out_________________?
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Answer: C. constant pressure
Explanation
Superheating involves adding thermal energy to saturated steam to raise its temperature above the saturation point corresponding to that pressure. In industrial steam generators, this process occurs inside tube bundles placed within high-temperature flue gas zones at a steady pressure. Because the steam flows continuously through open superheater headers, the entire heat addition takes place at constant pressure. Superheaters are categorized as radiant or convective heat exchangers located strategically within the boiler furnace gas path. Using superheated steam prevents moisture droplet condensation in turbine blades, thereby avoiding severe erosion and efficiency losses. The thermodynamic state of superheated steam is defined by both its pressure and a temperature higher than the saturation temperature.
Constant volume heating occurs in closed rigid vessels, which does not reflect the continuous flow setup of industrial boilers. Constant temperature processes apply to phase changes like boiling water, whereas superheating always involves an increasing temperature. Constant entropy and enthalpy options describe ideal adiabatic expansions or throttling processes rather than the heat addition phase.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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