内燃机排气余热回收梯级分段温差电单偶模拟分析

Simulation and Analysis of Segmented Thermoelectric Unicouple Used for Waste Heat Recovery of Internal Combustion Engine

本文选取了Bi_2Te_3和CoSb_3两种温差电材料设计了一种梯级分段温差电单偶,并对其建立了数学模型,导出温差电单偶的功率和效率计算公式,分析冷热端陶瓷片表面温度、温差电单偶长度以及表面对流传热系数对分段温差电单偶性能的影响。分析结果表明提高热面温度、降低冷面温度和提高热表面对流传热系数均可以提高分段温差电单偶的最大输出功率和最大转换效率。缩短温差电单偶的长度可以增大最大输出功率,但会导致最大转换效率的明显下降。

In this paper,a segmented thermoelectric unicouple is designed using two kinds of thermoelectric materials-Bi_2Te_3 and CoSb_3.The mathematical model of the unicouple is established.Based on the mathematical model,calculation formula of the output power and conversion efficiency are derived.And the thesis analyzes the influence of surface temperature of hot and cold side ceramics,thickness of unicouple and convection heat transfer coefficient of hot surface on the performance of segmented thermoelectric unicouple.The results show that increase hot surface temperature,reduce cold surface temperature and increase the convection heat transfer coefficient can improve the maximum output power and conversion efficiency of the thermoelectric unicouple.Cutting down the thickness of unicouple can increase the maximum output power,but it will result in the reducing of maximum conversion efficiency.