Ma Yu-Han, Zhai Ruo-Xun, Chen Jinfu, Sun C P, Dong Hui
Beijing Computational Science Research Center, Beijing 100193, China.
Graduate School of China Academy of Engineering Physics, No. 10 Xibeiwang East Road, Haidian District, Beijing 100193, China.
Phys Rev Lett. 2020 Nov 20;125(21):210601. doi: 10.1103/PhysRevLett.125.210601.
The finite-time dynamics, apart from its fundamental importance in nonequilibrium thermodynamics, is of great significance in designing heat engine cycles. We build an experimental apparatus to test the predicted long-time 1/τ scaling of the irreversible entropy generation in the finite-time (τ) thermodynamic process by compressing dry air in a temperature-controlled water bath. We present the first direct experimental validation of the scaling, utilized in many finite-time thermodynamic models at the long-time regime. The experimental data also demonstrate a clear deviation from the scaling at the short-time regime. We show the optimal control scheme to minimize the irreversible entropy generation in finite-time process. Such optimization shall bring new insight to the practical design of heat engine cycles.
有限时间动力学，除了在非平衡态热力学中具有根本重要性外，在热机循环设计中也具有重要意义。我们构建了一个实验装置，通过在温度可控的水浴中压缩干燥空气，来测试有限时间（τ）热力学过程中不可逆熵产生的预测长时间1/τ标度。我们给出了这种标度的首次直接实验验证，该标度在许多有限时间热力学模型的长时间 regime 中都有应用。实验数据还表明在短时间 regime 中明显偏离了该标度。我们展示了在有限时间过程中最小化不可逆熵产生的最优控制方案。这种优化将为热机循环的实际设计带来新的见解。
