Krishnamurthy Sudeesh, Ganapathy Rajesh, Sood A K
Department of Physics, Indian Institute of Science, Bangalore, 560012, India.
International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, 560064, India.
Nat Commun. 2023 Oct 27;14(1):6842. doi: 10.1038/s41467-023-42350-y.
All real heat engines, be it conventional macro engines or colloidal and atomic micro engines, inevitably tradeoff efficiency in their pursuit to maximize power. This basic postulate of finite-time thermodynamics has been the bane of all engine design for over two centuries and all optimal protocols implemented hitherto could at best minimize only the loss in the efficiency. The absence of a protocol that allows engines to overcome this limitation has prompted theoretical studies to suggest universality of the postulate in both passive and active engines. Here, we experimentally overcome the power-efficiency tradeoff in a colloidal Stirling engine by selectively reducing relaxation times over only the isochoric processes using system bath interactions generated by electrophoretic noise. Our approach opens a window of cycle times where the tradeoff is reversed and enables the engine to surpass even their quasistatic efficiency. Our strategies finally cut loose engine design from fundamental restrictions and pave way for the development of more efficient and powerful engines and devices.
所有实际热机，无论是传统的宏观热机还是胶体和原子级的微观热机，在追求最大功率时都不可避免地要在效率上进行权衡。有限时间热力学的这一基本假设在两个多世纪以来一直是所有发动机设计的难题，迄今为止实施的所有最优方案最多只能将效率损失降至最低。由于缺乏一种能让发动机克服这一限制的方案，理论研究表明这一假设在被动和主动发动机中都具有普遍性。在此，我们通过利用电泳噪声产生的系统浴相互作用，仅在等容过程中选择性地缩短弛豫时间，从而在实验上克服了胶体斯特林发动机中的功率 - 效率权衡。我们的方法打开了一个循环时间的窗口，在此窗口中权衡被逆转，使发动机甚至能够超越其准静态效率。我们的策略最终使发动机设计摆脱了基本限制，为开发更高效、更强大的发动机和设备铺平了道路。
