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具有微尺度传热特征的超常传热过程中,热流矢与温度梯度之间存在延迟效应,且热流的运动受到空间效应的影响.基于热质概念的普适导热定律,结合Clausius不等式和Helmholtz自由能公式,构建了计及热流矢和温度对时间和空间惯性效应的广义热弹性动力学模型,推导了各向同性材料超常传热行为的热弹性控制方程组.通过与已有广义热弹性动力学模型进行对比分析可得,当热流密度不大的条件下,热流矢与温度对空间的惯性效应可忽略时,基于热质概念的广义热弹性模型可分别退化为L-S,G-L和G-N的模型;对于尺度微观、稳态导热条件时,热流矢与温度对空间的惯性效应不可忽略,此时导热系数将受到热质运动惯性效应的影响,利用所建模型可揭示稳态导热时呈现的非傅里叶现象,并可避免基于已有广义模型得到的导热系数随结构特征尺寸变化的非物理现象.
In hyperthermic heat transfer with microscale heat transfer, there is a delay effect between heat flux and temperature gradient, and the heat flow is affected by space effect.According to the universal heat conduction law based on the concept of heat and mass, combining the Clausius inequality and Helmholtz freedom A generalized thermoelastic model considering the effects of heat flux and temperature on the inertia of space and time can be constructed and the thermoelastic control equations for the superheat transfer behavior of isotropic materials are deduced.Comparing with the existing generalized thermoelastic When the heat flux and temperature have negligible inertial effects on space, the generalized thermoelastic model based on the concept of thermal mass can degenerate into the models of LS, GL and GN, respectively ; For the standard microscopic and steady thermal conditions, the inertial effect of heat flux and temperature on space can not be neglected. At this time, the thermal conductivity will be affected by the inertial effect of thermal mass motion. The model can be used to reveal the non- Fourier phenomenon and can avoid the non-physical phenomenon that the thermal conductivity obtained by the existing generalized model changes with the size of the structural feature.