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3.8. Heat Exchanger - HEX
3.8 Heat Exchanger - HEX
Beside the heat exchangers implicitly appearing in the absorber, condenser
and evaporator, three different heat exchanger components (HEXes)
exist:
• Gas-Gas HEX appearing in the SOFC subsystem.
• Water-Gas HEX for transferring heat from the exhaust gas to
heating circuits.
• Solution HEX for internal heat exchange between strong and weak
LiBr solution.
Figure 3.11: Heat exchangers (all counter flow). Types: Gas-Gas, Water-Gas, and Solution
heat exchangers
T [° C ]
T hot , i
ΔT min ,hot ,i
T hot , o
T cold ,o
ΔT min ,hot ,o
T cold ,i
HEX
˙Q[kW ]
Figure 3.12: Heat Exchangers: Closest approach temperature difference can appear in either
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