carrier psychrometric chart high temperature

For HVAC design and for all everyday practical purposes, Relative Humidity (RH) and Degree of Saturation (DS) can be considered to be almost the same. Figureĭegree of Saturation (DS) is the ratio of moisture content (or humidity ratio) of the air at a given DB temp to the moisture content (humidity ratio) of the saturated air at the same DB temp. However, it is very close to the ratio of moisture contents and the difference is about 2%. RH is a ratio of water vapor pressures and not a ratio of moisture contents. Relative Humidity (RH) is the ratio of the actual water vapor pressure at a given DB temp to the water vapor pressure of the air if the air was saturated at the same DB temp. This maximum moisture content increases with increasing temperature. Saturated Air contains the maximum possible moisture (water vapor or steam) that the air can hold at a given DB temp. It is the moisture content of the air and it is indicative of the latent heat content of the air. Humidity Ratio (W) is the weight (lbs) of water vapor per unit weight (1 lb) of dry air. It is the best indicator of comfort conditions. DP temp is indicative of the moisture content and latent heat in the air. WB temp is indicative of the total heat (sum of both sensible heat and latent heat) content of the air.ĭew Point (DP) temperature is the temperature at which condensation of moisture begins when the air is cooled by removing sensible heat only. The evaporation of the moisture surrounding the bulb cools the air. Wet Bulb (WB) temperature is the temperature of air as registered by a thermometer whose temperature sensing bulb is covered by a material (cloth) soaked in water and exposed to a rapidly moving current of air. DB temp is indicative of the sensible heat content of the air. Dry Bulb (DB) temperature is the temperature of air as registered by an ordinary (mercury) thermometer.

Carrier psychrometric chart high temperature