Wet Bulb Vs Dew Point

The dew point is the temperature the air needs to be cooled to at constant pressure in order to achieve a relative humidity rh of 100.

Wet bulb vs dew point.

These can be calculated automatically using wildland fire rh calculator apps for ios and android available for free. Posted november 3 2016 11 51 a m. The dew point temperature of air depends upon its mositure content. The key difference between dewpoint and wet bulb temperature is that dewpoint temperature is the temperature to which we should cool the air to saturate the air with water vapor whereas wet bulb temperature is the temperature that we get from a moistened thermometer bulb that is exposed to air flow.

It includes a dry bulb thermometer a wet bulb thermometer and a psychrometric chart a graph that plots the relationships between the dry and wet bulb temperature relative humidity and dew point at constant pressure. Dry bulb wet bulb and dew point temperatures. The knowledge of only two of these values is enough to determine the state of the moist air including the content of water vapor and the sensible and latent energy enthalpy in the air. Such an instrument is called a wet bulb thermometer.

Dew point and wet bulb temperatures are very important in indicating the state of the humid air. Higher the mositure content of the air higher is the dew point temperature. Edt updated november 3 2016 5 10 p m. The knowledge of only two of these values is enough to determine the state including the content of water vapor and the sensible and latent energy enthalpy.

A widely used device for measuring wet and dry bulb temperature is a sling psychrometer which consists of a pair of mercury bulb thermometers one with a wet sock to measure. The dry bulb wet bulb and dew point temperatures are important to determine the state of humid air. At this point the air cannot hold more water in the gas form. Wet bulb temperature is measured using a thermometer that has its bulb wrapped in cloth called a sock that is kept wet with distilled water via wicking action.

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. Wet bulb temperature vs dew point differences explained.