Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! Specific humidity of moist air vs. relative humidity, water vapor and air density.
Humidity is the quantity of water vapor present in air. It can be expressed as an
absolute, specific or a relative value.
If we know the relative humidity of the moist air and the water vapor density and the density of the air, the specific humidity can be expressed as:
x = 0.622 φ ρ ws / (ρ - ρ ws) 100% (1)
x = specific humidity (humidity ratio) of air vapor mixture (kg h2o/kg dry_air)
φ = relative humidity (%)
ρ ws = density of water vapor (kg/m 3)
ρ = density of the moist or humid air (kg/m 3) Related Topics Moist and humid air - psychrometric charts, Mollier diagrams, air-condition temperatures and absolute and relative humidity and moisture content. Related Documents Absolute humidity is the actual mass of water vapor present in the air water vapor mixture. The mass of water vapor present in moist air - to the mass of dry air. Pressure, temperature and volume in a perfect ideal gas like moist air (air with water vapor). The change in state wwhen mixing moist air - enthalpy, heat, temperature and specific humidity. Density of the mix of dry air and water vapor - moist humid air. Sensible and latent heat of moist air. Psychrometric table with humid air properties like saturation pressure, specific volume, enthalpy and entropy. Relative humidity in moist air is the ratio of partial vapor pressure to air pressure. Specific volume of moist air is defined as the total volume of humid air per mass unit of dry air Recommended relative humidity level.
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