CLIMIA CMG 100, Руководство по эксплуатации

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Humidity measuring unit CMG 100
Water vapour condensation
Because the capacity for the
maximum possible volume of
water vapour increases as the air is
heated, the volume of water vapour
contained remains constant and so
relative humidity falls.
In contrast, because the capacity for
the maximum possible volume of
water vapour decreases as the air is
cooled, the volume of water vapour
contained remains constant and so
relative humidity increases.
If the temperature continues to
fall, the capacity for the maximum
possible volume of water vapour
is reduced so much so that it is
ultimately equal to the volume of
water vapour contained in the air.
This temperature is referred to as
the dew point. If the air is cooled
to below dew point, the volume of
water vapour in the air will become
greater than the maximum possible
volume of water vapour.
At this point, the water vapour
begins to precipitate.
This condenses to water and
moisture is removed from the air.
Examples of condensation include
steamed-up window panes in
winter, or the moisture on the
outside of a cold drinks bottle.
As the relative
humidity of the air increases, so too
does the dew point, making it easier
for the temperature to fall below it.
Condensation heat
The energy transferred to the air
from the condenser consists of:
1. The amount of heat derived
beforehand in the evaporator.
2. The electrical drive energy.
3. The condensation heat released
by liquefying the water vapour.
Energy must be supplied when
liquid is converted into a gas. This
energy is designated as evaporation
heat. It does not cause any increase
in temperature, but is required
to convert a liquid into a gas.
Conversely, energy is released when
gas is liquefied, this is designated as
condensation heat.
The amount of energy from
evaporation heat and condensation
heat is the same.
For water, this is:
2250 kJ/kg (4.18 kJ = 1kcal)
From this it is evident that the
condensation of water vapour
causes a large quantity of energy to
be released.
If the moisture that it is to be
condensed is not introduced by
evaporation in the room itself,
but from outside, e.g. through
ventilation, the condensation heat
released contributes to the heating
of the room. With drying operations,
a heat cycle is created, whereby
heat is consumed for evaporation
and released for condensation.
When dehumidifying fed air, a
larger contribution of heat is
created, which manifests itself as a
temperature increase.
Generally speaking, the time
required for the drying process is
not only dependent on the output
of the unit, but is determined to
a greater extent by the speed at
which the material or building
section loses its moisture.