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3. COMPONENT DESCRIPTION
3.3 Blower
Figure 3.3: Blower component. ”i” is the inlet and ”o” is the outlet. Ẇ is the blower power.
It is assumed that no chemical reaction takes place in the blower, so
the mass flow of each species out of the blower is equal to its mass flow
into the blower. All species have been modeled as ideal gasses. They are
hence in gas phase all the time, and the enthalpy only depends on the
temperature, while the entropy also depends on the pressure. The blower
uses an isentropic efficiency to determine the enthalpy and temperature
(i=inlet, 2=state just after the compression).
η i s = Ḣ2,i s − Ḣ i
Ḣ 2 − Ḣ i
(3.10)
The blower work is then determined as the enthalpy flow difference
during the compression.
Ẇ = (Ḣ 2 − Ḣ 1 ) (3.11)
The energy balance then includes the parameter ˙Q loss which is the
amount of heat lost to the surroundings (assumed to happen after the
compression). So the outlet temperature is determined from the enthalpy
flow in the outlet (o) which will be:
Ḣ o = Ḣ i +Ẇ − ˙Q loss (3.12)
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