Optimizing the performance of Bi2Te3 TECs through numerical simulations using COMSOL multiphysics

Manufacturers need to determine the best geometries for thermoelectric coolers (TECs) to achieve optimal performance. In this study, we employed the COMSOL Multiphysics software to simulate the performance enhancement of Bi2Te3 TEC. The TEC is constructed with alumina (Al2O3), copper (Cu), and bismuth telluride (Bi2Te3) materials. In particular, Al2O3 acts as an electric insulator for the top and bottom layers, Cu functions as a conductor, and Bi2Te3 serves as the p- and n-type thermoelectric (TE) legs between the Cu layers. The study examined how different TE leg heights (1.5 mm, 2 mm, and 2.5 mm) and shapes (square and rectangular) affected the TEC's performance. It looked at various factors, such as temperature gradient, electric potential, normalized current density, and total net energy rate. Additionally, the thickness effects of the insulator, conductor, and the TE leg pitch of the TEC have also been investigated. According to the obtained results, it has been determined that the square type of leg geometry has provided the best performance among the tested geometries, and it has been recommended that its leg geometry be 1.00 mm × 1.00 mm × 1.5 mm, the thickness be 0.375 mm for Al2O3 and 0.125 mm for Cu, and the pitch be 0.50 mm, as they are expected to yield satisfactory performance. The research study involved obtaining performance parameters for 18 TE elements utilized in the fabrication of TEC. The TEC-simulated results revealed the following performance metrics: ΔTmax = 73.94 K, Umax = 2.52 V, Imax = 3.00 A, Qmax = 4.42 W, R = 0.84 Ω, and Z = 0.002377 1/K.