Geometrical Effect in Magneto-Peltier Cooling of Bi and Bi_<0.88>Sb_<0.12> Polycrystals

概要

論文の詳細を見る
The cooling temperatures of rectangular parallelepiped Bi and Bi_<0.88>Sb_<0.12> polycrystals with various widths Wand thickness t were measured at 293 K as a function of electric current in the magnetic field B up to 2.171, where the magnetic field is aligned along the thickness of a sample and the current flows along its length L through the copper leads soldered to both end whole surfaces of the cross section (W × t). Under such a configuration the temperatures were measured at both end surfaces. A thermoelement is not in contact with a heat sink. The cooling temperature at the cooled surface increased with increasing the magnetic field, and the rate of increase depended strongly on the cross-sectional area (W × t) of a sample, particularly in high magnetic fields. The highest cooling temperature was found to be achieved when a thermoelement has an optimum cross-sectional area (fitted to its length) so that Joule heating and the thermal conduction energies become equal under the operating conditions. The cooling temperature of Bi_<0.88>Sb_<0.12> with optimum dimensions increased from 3.1 K in B = 01 to 6.4K in B = ±2.17T, so that it slightly exceeded a cooling temperature of 5.7 K which was obtained for a typical Bi2Te3 with a thermoelectric figure of merit of ZT = 0.87 at 298 K.
社団法人応用物理学会の論文
2002-10-15