论文标题
有限时间Carnot周期的实验实施
Experimental implementation of finite-time Carnot cycle
论文作者
论文摘要
Carnot循环是理想的热发动机的原型，可从两个热浴之间的热通量从具有最大效率的热通量中吸收机械能，称为Carnot效率$η_{\ Mathrm {c}} $。只有在无限时间的热力学平衡过程中才能达到这种效率，而不可避免地会伴随着消失的功率 - 每单位时间的能量输出。在现实世界中，获得高功率的追求导致一个悬而未决的问题，是否存在具有给定功率的有限时间加热发动机的最大最大效率。我们通过密封的干燥空气作为工作物质实验实现有限的卡诺循环，并验证功率和效率之间的权衡关系。效率高达$（0.524 \ PM0.034）η_{\ MathRM {C}}} $以生成最大功率，与理论预测$η_{\ Mathrm {C}}}}}}}/2 $一致。我们的结果应为研究由非平衡过程组成的有限时间热力学提供一个新的平台。
The Carnot cycle is a prototype of ideal heat engine to draw mechanical energy from the heat flux between two thermal baths with the maximum efficiency, dubbed as the Carnot efficiency $η_{\mathrm{C}}$. Such efficiency can only be reached by thermodynamical equilibrium processes with infinite time, accompanied unavoidably with vanishing power - energy output per unit time. In real-world applications, the quest to acquire high power leads to an open question whether a fundamental maximum efficiency exists for finite-time heat engines with given power. We experimentally implement a finite-time Carnot cycle with sealed dry air as working substance and verify the existence of a tradeoff relation between power and efficiency. Efficiency up to $(0.524\pm0.034)η_{\mathrm{C}}$ is reached for the engine to generate the maximum power, consistent with the theoretical prediction $η_{\mathrm{C}}/2$. Our results shall provide a new platform for studying finite-time thermodynamics consisting of nonequilibrium processes.
