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What will be the specific enthalpy of steam at pressure of 2 MPa and dryness fraction of 0.9? [Where, properties of steam at 2 MPa are: specific enthalpy of saturated liquid = 900 kJ/kg, specific enthalpy of saturated vapour = 2800 kJ/kg.]

What will be the specific enthalpy of steam at pressure of 2 MPa and dryness fraction of 0.9? [Where, properties of steam at 2 MPa are: specific enthalpy of saturated liquid = 900 kJ/kg, specific enthalpy of saturated vapour = 2800 kJ/kg.] Correct Answer 2610 kJ/kg

Concept:

Specific enthalpy (h) at any point is calculated by the following formula

h = hf + x(hg - hf)     -------(1)

where hf = specific enthalpy of saturated liquid; hg = specific enthalpy of saturated vapour;

x = dryness fraction

Calculation:

Given:

hf = 900 kJ/kg; hg = 2800 kJ/kg; x = 0.9

Substituting the given values in the equation 1

h = 900 + 0.9 × (2800 - 900)

∴ h = 2610 kJ/kg

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