With enthalpy units in btu lb.
Wet bulb dry bulb chart.
Wet bulb temperature twb.
At lower humidity the wet bulb temperature is lower than dry bulb temperature because of evaporative cooling.
Constant dry bulb temperatures appear as vertical lines in the psychrometric chart or horizontal lines in the mollier diagram.
Wet bulb temperature axis on psychrometric chart wet bulb temperature axis is highlighted in following figure.
By definition wet bulb temperature is the lowest temperaturea portion of air can acquire by evaporative cooling only.
The wet bulb temperature wbt is the temperature read by a thermometer covered in water soaked cloth wet bulb thermometer over which air is passed.
Dry bulb temperature is 30 0 c and wet bulb temperature is 25 0 c.
At 100 relative humidity the wet bulb temperature is equal to the air temperature dry bulb temperature.
The following tables calculate dew point and relative humidity based on the observed wet bulb and dry bulb temperatures and the elevation at the site of the observation.
These can be calculated automatically using wildland fire rh calculator apps for ios and android available for free.
Dry bulb temperature ranging 20 o f to 120 o f.
Barometric pressure 29 921 inches of mercury.
The wet bulb temperature is always lower than the dry bulb temperature but will be identical with 100 relative humidity the air is at the saturation line.
Combining the dry bulb and wet bulb temperature in a psychrometric diagram or mollier chart gives the state of the humid air.
Wet bulb temperature is lower than dry bulb temperature or equal to the dry bulb temperature.
The psychrometric chart below is made for standard atmospheric conditions.
Calculate the relative humidity.
The dry bulb temperature is an indicator of heat content and is shown along the bottom axis of the psychrometric chart or along the left side of the mollier diagram.
This equality occurs at only in air become saturated.
The relative humidity is approximately 50 the humidity ratio is approximately 65 grainsh2o lbdry air relative humidity temperature in fahrenheit.