THERMAL ENGINEERING RESEARCH OF THERMOELECTRIC GENERATION BY USE OF VERY THIN AMORPHOUS SEMICONDUCTOR LAYER.

Research Project

Project/Area Number	60420029
Research Category	Grant-in-Aid for General Scientific Research (A)
Allocation Type	Single-year Grants
Research Field	Thermal engineering
Research Institution	UNIVERSITY OF ELECTRO-COMMUNICATIONS
Principal Investigator	MORI YASUO UNIVERSITY OF ELECTRO-COMMUNICATIONS, 電気通信学部, 教授 (20016207)
Co-Investigator(Kenkyū-buntansha)	MATSUBARA KAKUEI YAMAGUCHI UNIVERSITY, 工学部, 教授 (30025986)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥11,900,000 (Direct Cost: ¥11,900,000) Fiscal Year 1986: ¥2,700,000 (Direct Cost: ¥2,700,000) Fiscal Year 1985: ¥9,200,000 (Direct Cost: ¥9,200,000)
Keywords	THERMOELECTRIC POWER GENERATION / AMORPHOUS LAYER / FIN EFFECT / LEADING EDGE EFFECT / LARGE TEMPERATURE DIFFERENCE / LARGE ZEEBECK COEFFICIENT / 熱電発電一般理論 / 広温度域 / アモルファス半導体 / 太陽熱利用 / 極薄膜半導体 / 電気絶縁薄膜
Research Abstract	In the conventional thermoelectric power generation, a thermoelectric device of crystalline structure is used and generates electric power by use of the themperature difference caused between the both ends of the device due to its thermal resistance, but the temperature difference is fairly small. In this research, a new proposal is made as to effectively use a large temperature difference between the both ends in the width direction of a fin of thin metal plate one end of which is welded to a water pipe for cooling. The fin is exposed to hot gas and a semiconductor of a good thermoelectric performance and of amorphous structure is put on by a cluster-ion vapor deposition method. The electrodes are attached at the both ends of the fin and a thin polyimide layer is spreaded between the fin surface and the amorphous thin layer. For the low or medium temperature region Ge-in mixtures were used and experiments on thermoelectric performances and power generation were made by use of a solar … More heat simulating equipment made for this research. In the experiment of solar heat flux, the temperature difference of 20゜C was obtained but a high performance was not obtained due to the poor thermoelectric performance of the mixture and the thin amorphous layer. In the high temperature experiment mainly aiming at effective use of exhaust combustion gas of temperature region of 250゜C to 400゜C, Fe-Si was selected as the material and the construction same as used for medium temperatures was adopted. A hot gas wind funnel of vertical construction was manufactured for experiments. Many samples of Fe-Si amouphous layer deposited on thin flat glass plate were made for getting Zeebeck coefficient, specific resistance and effect of Fe to Si atomic ratio on performance. In thermal engineering experiments, in a hot gas of about 350゜C, about 180゜C temperature difference which is sufficiently large for use of thermoelectric power generation was proved to attain in the fin due to the fin and leading edge effcts. A general investigation of thermoelectric performance considering temperature dependence of Zeebeck performance was made. The relations of the open circuit voltage and the short circuit current and the maximum power output were newly derived for the thermoelectric generator construction proposed in this research. The value of Zeebeck coefficient of about 10 mV/゜C was obtained for Fe-Si at about 300゜C. But as the amouphous layer was so thin the power was found not so large. Finally, the performance change with time and future problems to be studied were discussed. Less