Application Instructions
26
Hydromette BL Compact RH-T
The aw value is an important measure concerning the shelf life of
foodstuffs and influences the incidence of microorganisms that
have differing requirements for freely available water. With a lack of
free water, growth processes are slowed or prevented, whereas
others are accelerated. Therefore, the aw value is an important
measure in the chemical and food industries.
4.1.6
Wet-bulb Temperature
The
wet-bulb temperature
is the lowest temperature that can be
achieved with evaporative cooling.
The release of water from the damp surface is in balance with the
ability of the surrounding atmosphere to absorb water and thus
saturates the surrounding air with water vapour. Because of the
evaporative chill, the wet-bulb temperature is dependent on the
relative air humidity and lies under the air temperature. The
temperature difference is the larger, the drier the surrounding air is.
Using the temperature difference, the relative humidity can thus be
determined.
The wet-bulb temperature (in the drawing (
T2
)) is determined with a
psychrometric measurement with a thermometer provided with a
damp material cover.
The wet-bulb temperature is mainly of interest where large amounts
of liquids evaporate, such as in wood drying machinery.
