Mohanta Sandipan, Saryal Sushant, Agarwalla Bijay Kumar
Department of Physics, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pune, Maharashtra 411008, India.
Phys Rev E. 2022 Mar;105(3-1):034127. doi: 10.1103/PhysRevE.105.034127.
For steady-state autonomous absorption refrigerators operating in the linear response regime, we show that there exists a hierarchy between the relative fluctuation of currents for cold, hot, and work terminals. Our proof requires the Onsager reciprocity relation along with the refrigeration condition that sets the direction of the mean currents for each terminal. As a consequence, the universal bounds on the mean cooling power, obtained following the thermodynamic uncertainty relations, follow a hierarchy. Interestingly, within this hierarchy, the tightest bound is given in terms of the work current fluctuation. Furthermore, the relative uncertainty hierarchy introduces a bound on cooling efficiency that is tighter than the bound obtained from the thermodynamic uncertainty relations. Interestingly, all of these bounds saturate in the tight-coupling limit. We test the validity of our results for two paradigmatic absorption refrigerator models: (i) a four-level working fluid and (ii) a two-level working fluid, operating in the weak (additive) and strong (multiplicative) system-bath interaction regimes, respectively.
对于在线性响应区域运行的稳态自主吸收式制冷机，我们表明，冷端、热端和功端电流的相对涨落之间存在一种层级关系。我们的证明需要昂萨格互易关系以及设定每个端平均电流方向的制冷条件。因此，遵循热力学不确定性关系得到的平均制冷功率的通用界限也遵循一种层级关系。有趣的是，在这个层级关系中，最严格的界限是根据功电流涨落给出的。此外，相对不确定性层级关系引入了一个比从热力学不确定性关系得到的界限更严格的制冷效率界限。有趣的是，所有这些界限在紧密耦合极限下都会饱和。我们针对两种典型的吸收式制冷机模型检验了我们结果的有效性：（i）一种四级工作流体，以及（ii）一种两级工作流体，分别在弱（加性）和强（乘性）系统 - 热库相互作用区域运行。
