Gauge Pressure and Specific Volume of Saturated Liquid

Observe the relationship between gauge pressure and the specific volume of the saturated steam.


Differences in density are generally referred to by the measurement of specific volume. The unit of measure for specific volume is cubic feet per pound (ft3/lb). As pressure increases in the system, the specific volume of the liquid rises marginally.

Water is incompressible, and therefore is not affected by steam pressure. As pressure increases, however, so does the steam temperature. This temperature increase results in greater motion in the molecules of the water and a slight increase in its specific volume.