2024-03-28T08:30:19Zhttps://repositori.uji.es/oai/requestoai:repositori.uji.es:10234/1586252023-04-03T11:12:50Zcom_10234_7034com_10234_9col_10234_8619
00925njm 22002777a 4500
dc
García-Cañadas, Jorge
author
Min, Gao
author
2016-03-09
Understanding the dynamics of thermoelectric (TE) phenomena is important for the detailed knowledge of the operation of TE materials and devices. By analyzing the impedance response of both a single TE element and a TE device under suspended conditions, we provide new insights into the thermal dynamics of these systems. The analysis is performed employing parameters such as the thermal penetration depth, the characteristic thermal diffusion frequency and the thermal diffusion time. It is shown that in both systems the dynamics of the thermoelectric response is governed by how the Peltier heat production/absorption at the junctions evolves. In a single thermoelement, at high frequencies the thermal waves diffuse semi-infinitely from the junctions towards the half-length. When the frequency is reduced, the thermal waves can penetrate further and eventually reach the half-length where they start to cancel each other and further penetration is blocked. In the case of a TE module, semi-infinite thermal diffusion along the thickness of the ceramic layers occurs at the highest frequencies. As the frequency is decreased, heat storage in the ceramics becomes dominant and starts to compete with the diffusion of the thermal waves towards the half-length of the thermoelements. Finally, the cancellation of the waves occurs at the lowest frequencies. It is demonstrated that the analysis is able to identify and separate the different physical processes and to provide a detailed understanding of the dynamics of different thermoelectric effects.
GARCÍA-CAÑADAS, J.; MIN, G. Thermal dynamics of thermoelectric phenomena from frequency resolved methods. AIP Advances, 2016, vol. 6, no 3, p. 035008.
2158-3226
http://hdl.handle.net/10234/158625
http://dx.doi.org/10.1063/1.4943958
Ceramic materials
Diffusion
Heat storage
Thermal diffusion
Thermoelectricity
Heat production
High frequency HF
Impedance response
Physical process
Thermal dynamics
Thermal penetration depths
Thermoelectric
Thermoelectric response
Thermal dynamics of thermoelectric phenomena from frequency resolved methods