Saturated Water in A Piston- cylinder
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A mechanical engineering student gets an internship in a power plant. His first task is to design a piston-cylinder device which is used to vaporize the saturated water to saturated vapor under a given pressure. The volume of the device and how much heat needed for the vaporization process are the first thing he has to figure out.

What is known:

  • The mass of water m = 10.0 kg
  • Operation pressure P = 100.0 kPa

  • What is the volume change from liquid water to vapor
  • How much heat is added for the vaporization process

  • Latent heat of vaporization (LV) of water under 100 kPa is 2257.0 kJ/kg.
  • Specific volume (Will be introduced in next section) of saturated water (vf) under 100 kPa is 0.001 m3/kg.
  • Specific volume of saturated vapor (vg) under 100 kPa is 1.673 m3/kg.