半导体温差发电过程的模型分析与数值仿真

本文提出一种新型的半导体温差发电模型,在温差发电过程的数值模拟中考虑了热电单元之间封闭腔体内空气传热的影响.同时进一步运用有限元的数值计算方法对不同电臂对数和不同型号温差发电模型的温度场、电压场进行了数值仿真计算,并对仿真结果进行分析.结果表明:采用127对热电单元模型计算的能量转换效率随冷热端温差增大而迅速提高,与采用1对热电单元模型计算的能量转换效率之差从冷热端温差为20℃的0.39%提高到冷热端温差为220℃时的5.16%,能量转换效率比1对热电单元平均高出3.02%.冷端温度恒定在30℃时,温差发电芯片的输出电压、功率以及能量转换效率均随着电偶臂的横截面积的增大而提高,且电偶臂冷热两端的温差越大提高幅度也越大,而温差发电芯片内阻则与电偶臂横截面积成反比关系,当温差为220℃时对应的输出功率最高达28.9 W.

Analysis and simulation of semiconductor thermo electric p ower generation pro cess

This paper presents an improved model of thermoelectric power generation, taking into consideration the effect of air heat transfer in a closed cavity between the thermoelectric couples. We have used the ANSYS software, under the condition of different numbers of thermoelectric couples and different models, to simulate numerically and analyze the temperature field and, the voltage field of thermoelectric power generation. Results show that the energy conversion efficiency of 127 pairs of thermoelectric couples increases rapidly as the temperature gradient between the hot and cold ends increases as compared with 1 pair of thermoelectric units; it is enhanced from 0.39% to 5.16% at an average of 3.02% while the temperature gradient varies from 20℃ to 220℃. The output voltage of the chip, power, and energy conversion efficiency would increase as the cross-sectional area increases while the cold junction temperature stays at 305℃, and the cold arm galvanic greater the temperature difference across the greater the increase rate, and thermoelectric power generation chip resistance, along with the cross-sectional area of the galvanic arm decreases. The output power can be up to 28.9W as the temperature difference is 220℃.
Keywords： thermoelectric generation thermoelectric model numerical simulation conversion efficiency