Esfarjani Keivan
Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, USA.
Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA 22904, USA.
Entropy (Basel). 2021 Dec 3;23(12):1630. doi: 10.3390/e23121630.
We consider the problem of heat transport by vibrational modes between Langevin thermostats connected by a central device. The latter is anharmonic and can be subject to large temperature difference and thus be out of equilibrium. We develop a classical formalism based on the equation of motion method, the fluctuation-dissipation theorem and the Novikov theorem to describe heat flow in a multi-terminal geometry. We show that it is imperative to include a quartic term in the potential energy to insure stability and to properly describe thermal expansion. The latter also contributes to leading order in the thermal resistance, while the usually adopted cubic term appears in the second order. This formalism paves the way for accurate modeling of thermal transport across interfaces in highly non-equilibrium situations beyond perturbation theory.
我们考虑通过一个中心装置连接的朗之万恒温器之间的振动模式进行热传输的问题。该中心装置是非谐的，可能会承受较大的温差，从而处于非平衡状态。我们基于运动方程方法、涨落耗散定理和诺维科夫定理发展了一种经典形式，以描述多端几何结构中的热流。我们表明，必须在势能中包含一个四次项，以确保稳定性并正确描述热膨胀。后者在热阻中也占主导阶，而通常采用的三次项出现在二阶。这种形式为超越微扰理论的高度非平衡情况下跨界面的热传输精确建模铺平了道路。
