Technical Information
Understanding Psychrometric Chart
- Dry Bulb Temperature: It is the air temperature measured with the thermometer’s dry probe.
- Wet Bulb Temperature: It is the air temperature measured with the thermometer’s wet probe. (It is measured by wrapping a wet cloth around the measuring probe of the thermometer.)
- Dew Point Temperature: It is the temperature at which moist air cooled at constant pressure begins to condense.
- Enthalpy: It is the amount of heat that must be given to the dry air/water vapor mixture (moist air) during heating and cooling processes. A specified reference list of the amount of heat in air is a displayed thermal property.
- Humidity Ratio / Specific Humidty: It is the ratio of the mass of water vapor in moist air to the mass of dry air.
- Specific Volume: It is the volume of air in unit mass.
Relative Humidity:
1) It is the ratio of the actual partial pressure exerted by the water vapor in the air to the partial pressure of the water vapor when it becomes saturated at the same temperature.
2) It is the ratio of the amount of water vapor in the current air to the amount of water vapor in the saturated air at the same temperature.
3) It is the division of the Xw mole ratio of water vapor in humid air to the Xws mole ratio of saturated air at the same pressure and temperature.
