摘要
分析了测量导热系数传统模型与相关文献中的修正模型的原理与不足,提出一个较为严密的三维传热学模型,利用MATLAB数值模拟验证了其合理性。推导出计算圆柱型试样导热系数的公式,并得到了适合实际应用的简化公式。以真空橡皮盘为例,定量分析了侧壁散热对导热系数测量值的影响程度,给出了试样规格与测算精度的关系曲线。当试样半径与厚度的比值大于28.9时,侧壁散热的影响将小于5%,故可忽略。
The principle of measuring thermal conductivity with steady state method is studied.It is found that there are some shortcomings in the traditional model and modified models.A more rigorous three-dimensional heat transfer model is proposed and verified for its rationality by using MATLAB simulation.A new formula of calculating thermal conductivity and its simplified formula for practical applications are developed.The effect of the sidewall cooling on the thermal conductivity,a vacuum rubber disk as an example,is quantitatively analyzed,and the function curve between the sample size and the measurement precision is plotted.When the ratio of the sample's radius versus thickness is greater than 28.9,the sidewall cooling effect will be less than 5%.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2011年第4期609-613,共5页
Journal of Materials Science and Engineering
基金
国家自然科学基金资助项目(10975014)
关键词
导热系数
稳态法
三维模型
散热影响
thermal conductivity
steady-state method
three-dimensional model
cooling effect