Saturation

Saturation
Saturation refers to the condition where a substance holds the maximum possible amount of another substance at a given temperature and pressure. Beyond this point, any additional amount will not dissolve, evaporate, or mix and will instead form a separate phase (e.g., liquid condensing from vapor or solute precipitating from solution).

Common meanings:

• Thermodynamics: A vapor is saturated when it is at equilibrium with its liquid; any cooling causes condensation.
• Humidity: Air is saturated with water vapor when the relative humidity reaches 100%.
• Solutions: A liquid is saturated with a solute when no more can dissolve at that temperature.

Examples in Automotive/Engineering:

• In air conditioning, refrigerant at saturation is ready to either evaporate or condense, depending on system conditions.
• In engine intake air, saturation with fuel vapor can affect combustion performance or emissions.