待测板温度场分布对导热系数测量的影响  

Influence of Temperature Field Distribution of the Tested Plate on Thermal Conductivity Measurement

作　　者：于莉莉[1] 郭远 裴能 喻孜[1] YU Lili;GUO Yuan;PEI Neng;YU Zi(College of Science,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]南京林业大学理学院,江苏南京210037

出　　处：《大学物理实验》2022年第1期20-24,共5页Physical Experiment of College

基　　金：江苏省创业训练项目(201910298009T);校大学生创新训练项目(2020NFUSPITP0103)。

摘　　要：稳态法测量导热系数的实验中,常将在空气中冷却的待测板置于散热板上,测量降温时散热板在稳定点的散热率。本文模拟了待测板的自然冷却过程,将不同时刻的待测板置于散热板上,其内部的温差场差异影响导热系数的大小,导热系数大小与待测板的冷却时间与成一次线性关系。对比计算了待测板恒温的情况下,不同温度的待测板对应的导热系数,研究结果表明待测板内部的温度场分布显著影响导热系数的测量,本文给出了室温20℃情况下,待测板理论最佳自然冷却时间和恒温值,为实验研究提供参考。In the experiment of measuring the thermal conductivity by steady-state method,the tested plate cooled in the air is usually put on the cooling plate to measure the heat dissipation rate at the stable temperature.We simulate the natural cooling process of the tested plate,which is placed on the cooling plate at different times.The difference of the internal temperature field affects the thermal conductivity.The linear relationship between the cooling time of the tested plate and the thermal conductivity is studied.Under the condition of constant temperature of the tested plate,the corresponding thermal conductivity coefficients at different temperatures are given,which indicates that the temperature field distribution in the tested plate significantly affects the measurement of thermal conductivity.The theoretical optimal cooling time and constant temperature value are given under the room temperature of 20℃,which can provide reference for experimental research.

关 键 词：导热系数 散热率 温度场 数值模拟 

分 类 号：O422[理学—声学]