🔍 Key Concepts

• Steam expansion in turbines and engines – what typically happens to temperature, pressure, and volume as steam does work • Difference between superheated steam and saturated steam (and what “superheat” means) • How moisture content changes when steam either gives up heat or expands doing work

💭 Think About

• When steam passes through a turbine and expands, what generally happens to its pressure and temperature? Does that trend make it more or less superheated? • As steam does work and expands, does its volume become larger or smaller for a given mass of steam? Think about basic gas/steam behavior. • Under what conditions would steam’s moisture content decrease—when you add heat or when you let it expand and cool while doing work?

✅ Before You Answer

• Be clear on the definition of superheated steam vs saturated steam—which one is ‘hotter than boiling’ at a given pressure? • Think about whether an expansion that performs work usually makes steam cooler or hotter overall. • Check whether doing work during expansion would make steam more likely to condense (more moisture) or dry out (less moisture).