Fraction of vapour mass in a saturated liquid-vapour mixture.
x=m_vapor/m_total within the dome; v=v_f+x v_fg (same for u, h, s). x=0 saturated liquid, 1 saturated vapour. Only meaningful at saturation. Determines properties of wet steam in turbine exhausts and evaporators.
Steam at 100 kPa with v=0.8 m³/kg has x≈0.47.
Quality describes how much of a mixture is vapour, so it is needed for wet steam and for two-phase refrigerants in cycles.
Fraction of vapour mass in a saturated liquid-vapour mixture.
Quality describes how much of a mixture is vapour, so it is needed for wet steam and for two-phase refrigerants in cycles.
The mass of vapour divided by the total mass, and it equals zero for saturated liquid and one for saturated vapour.
Properties such as enthalpy and specific volume are found by taking the liquid value plus quality times the difference between vapour and liquid values.
Typical applications include finding the enthalpy of wet steam leaving a turbine at a given pressure, checking the dryness of steam to protect turbine blades and calculating the mass of vapour in a refrigerant mixture.
Study "Property tables and steam tables" first (topic 15 of 105 in Thermodynamics & Fluids). It covers the groundwork this topic builds on.
Wetness 1-x damages turbine blades. Mixtures need P or T. Use for refrigerants too.
Steam at 100 kPa with v=0.8 m³/kg has x≈0.47.
The next topic is "Compressibility factor", which builds directly on this one.
It is classed as Beginner in Thermodynamics & Fluids (topic 16 of 105). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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