ENERGY CONVERSION AND MANAGEMENT, vol.83, pp.42-47, 2014 (Journal Indexed in SCI)
A combined thermal system consisting of a thermoelectric generator and a refrigerator is considered and the effect of location of the thermoelectric generator, in the refrigeration cycle, on the performance characteristics of the combined system is investigated. The operating conditions and their influence on coefficient of performance of the combined system are examined through introducing the dimensionless parameters, such as lambda(lambda = Q(HTE)/Q(H), where Q(HTE) is heat transfer to the thermoelectric generator from the condenser, Q(H) is the total heat transfer from the condenser to its ambient), temperature ratio (theta(L) = T-L/T-H, where T-L is the evaporator temperature and T-H is the condenser temperature), r(C) (r(C) = C-L/C-H where C-L is the thermal capacitance due to heat transfer to evaporator and C-H, is the thermal capacitance due to heat rejected from the condenser), theta(W) (theta(W) = T-W/T-H, where T-W is the ambient temperature), theta(C) (theta(C) = T-C/T-H, where T-C is the cold space temperature). It is found that the location of the thermoelectric generator in between the condenser and the evaporator decreases coefficient of performance of the combined system. Alternatively, the location of thermoelectric device in between the condenser and its ambient enhances coefficient of performance of the combined system. The operating parameters has significant effect on the performance characteristics of the combined system; in which case temperature ratio (theta(L)) within the range of 0.68-0.70, r(C) = 2.5, theta(W) = 0.85, and theta(C) = 0.8 improve coefficient of performance of the combined system. (C) 2014 Elsevier Ltd. All rights reserved.