【摘要】 本工作测量了气孔率为2.10,3.47,4.32,5.84,和8.67%的UO₂在573—2273K温度范围的热扩散率。算出了相应的热导率。基于UO₂的热传导模型,求得了热导率与温度、气孔率的关系式。与改进的Maxwell-Eucken气孔效应修正式对照,推算了气孔系数的表达式,还给出了UO₂的德拜温度。更多还原

【Abstract】 The thermal diffusivities of uranium dioxide containing various porosity aremeasured in temperature range of 573-2273K. Corresponding thermal conductivitiesare calculated based on the thermal conductive model. The correlation to fit thedata is obtained for the thermal conductivity of Uranium dioxide with temperatureand porosity as follows: K_p=1/4.42+20.3P+0.0197Te^2.14p+9.85×10^-4e^-2.36pT·e^-1.12/K_B·T The pore coefficients β and η in the Maxwell-Eucken’s and Loeb’s expressionfor porosity correction are derived. The results indicate the influence of porosityupon β is lower than η. We have <1173K β=1.99-0.44×10-³T >1173K β=1. 64-0. 14×10^-3T The calculated Debye temperature of Uranium dioxide is agreeable to previousvalue obtained by other author.更多还原