1. STEAM TABLES
PRACTICE EXAMPLES
Using your Thermodynamic Properties of Fluids Tables, determine.
1. The specific enthalpy of:
i. Saturated water at a temperature of 130oC,
ii. Dry saturated steam at a temperature of 130oC
2. The saturated water pressure, and the dry saturated steam pressure at 130oC
3. The specific volume of dry saturated steam at a pressure of 2.7bar.
4. The specific enthalpy of steam at a pressure of 2.7 bar and a dryness fraction of 0.9.
5. The specific enthalpy of steam at pressure of 20bar and a temperature of 400oC
SOLUTION
Page 5 of tables:
1.i Under column: ts read down to 130.0, read across under column hf = 546 kJ/kg.
ii Under column: ts read down to 130.0, read across under column hg = 2720kJ/kg.
2. " " " " p = 2.7bar.
3. " p " 2.7 bar, read across under column vg = 0.6686m3/kg.
4.
hwet = hf + xhfg
hwet = 546 + 0.9 x 2174
2502.6kJ/kg Ans
5. The saturation temperature for steam at 20bar is 212.4oC. In this case the steam is above its saturation
temperature it must therefore be superheated steam.
Page 8 of tables.
Under column: p read down to 20, read across to h and under column 400 = 3248kJ/kg
Determine the following specific enthalpies.
FLUID STATE ANSWER (kJ/kg)
Boiling water temperature = 165oC
Boiling water pressure = 5bar
Saturated water temperature = 195oC
Saturated water pressure = 1.6bar
Dry saturated steam pressure = 11bar
Dry saturated steam temperature = 165oC
Steam p = 5bar, dryness = 0.8
Steam ts = 128.7oC, dryness = 0.95
Steam p = 30bar, temp. = 350oC
Steam ts = 250.3oC, temp.= 400oC
Determine specific volumes for:
FLUID STATE ANSWER (m3/kg)
Steam p = 6bar, dryness = 0.9
Steam ts = 250.3oC, dryness = 0.88
Dry saturated steam p = 30bar
Dry saturated steam ts = 195oC
Steam p = 40bar, temp = 450oC
Steam ts = 263.9oC, temp = 500oC