For the fixed total number of thermoelectric thermocouples of the
combined device, the allocations of the number of thermoelectric thermocouples among
the two thermoelectric generators and the two thermoelectric coolers are also optimized
for maximizing cooling capacity and COP, respectively. The numerical calculations show
that the external heat transfers affect the performance of combined thermoelectric device
strongly. There are optimum allocations of the number of thermocouples and optimum
allocations of thermal conductance of heat exchangers corresponding to the maximum
cooling capacity and the maximum COP, respectively. When the total thermal conductance
of heat exchangers extends to infinity, the results of this paper approach the non-
equilibrium thermodynamic results obtained.
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