ZT值温度依存性对温差发电器热电性能的影响  

Temperature dependency of ZT value on thermoelectric generator performances

作　　者：何为[1] 王世 学 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072

出　　处：《热科学与技术》2014年第3期245-249,共5页Journal of Thermal Science and Technology

基　　金：国家973计划资助项目(2011CB707203)

摘　　要：为了评估热电材料ZT值温度依存性对热电发电器性能的影响,基于HZ-20商用热电材料的热物性参数,分别采用定物性与变物性的计算方法,对温差发电器在具有不同热源温度下的工作性能进行理论研究。研究结果表明,当采用定物性方法计算时(即不考虑ZT值温度依存性),输出功率及相应转换效率的计算值都较采用变物性计算时存在一定的偏差。当半导体热端温度低于定物性计算时采用的定性温度值时,偏差很小,但随着半导体热端温度的继续增加,偏差则越来越大,高热端温度下计算得到的计算偏差达30%左右。因此,热电材料ZT值温度依存性对温差发电器热电性能的影响不容忽视。To assess the influence of temperature dependency of thermoelectric figure of merit（ZT）value on the thermoelectric properties,HZ-20 type thermoelectric module was taken as an example for analysis and calculation.The working performance of thermoelectric generator with different heat-side temperatures were studied theoretically by considering constant and variable physical properties.It is shown that when the constant physical properties are used,there is a certain deviation on the calculated output power and conversion efficiency in comparison with the ones using variable physical properties.When the hot-side temperature of semiconductor is lower than 503 K,the deviation is very small.However,with an increasing hot-side temperature the deviation can grow by 30% in high hot-side temperature of thermoelectric generator.It can be concluded that the influence of temperature dependency for ZTvalue on thermoelectric properties cannot be ignored.

关 键 词：优值系数 变物性 温差发电器 热电性能 

分 类 号：TK11[动力工程及工程热物理—热能工程]