Thermoelectric generator with finite-sized reservoir

• DOI: 10.1016/j.physa.2020.125331
• Publication Date: 2020-09-26T04:38:36Z
• Authors: X.L. Huang; Qian Yu; H.W. Zhang; S.Q. Zhao; S.L. Wu
• Keywords: Thermoelectric generator; Internal resistance; Maximum power principle; Internal heating

Abstract We use the thermoelectric generator to study the effects of the internal irreversibility on the work output at maximum power when the heat source or sink is finite. We consider two working modes: the variable load and the fixed load. The variable load mode corresponds to the maximum theoretically while the fixed load mode is easy to control. We find in all cases, the work at maximum power does not depend on the internal resistance of the thermoelectric generator (i.e., the internal irreversibility), but the maximum power decreases with the internal resistance. In the variable load mode, the work at maximum power is half of the corresponding exergy when ω = 1 ( ω = 0 ) for the finite source (sink), where ω is the fraction of the internal Joule heat received by the heat sink. A larger initial temperature ratio of the two heat reservoirs improves (depresses) the coefficient of utilization of the exergy. For the fixed load mode, the maximum power requires that the load is smaller (larger) than the internal resistance.