Current Trends in Finite-Time Thermodynamics

The cornerstone of finite-time thermodynamics is all about the price of haste and how to minimize it. Reversible processes may be ultimately efficient, but they are unrealistically slow. In all situations-chemical, mechanical, economical-we pay extra to get the job done quickly. Finite-time thermodynamics can be used to develop methods to limit that extra expenditure, be it in energy, entropy production, money, or something entirely different. Finite-time thermodynamics also includes methods to calculate the optimal path or mode of operation to achieve this minimal expenditure. The concept is to place the system of interest in contact with a time-varying environment which will coax the system along the desired path, much like guiding a horse along by waving a carrot in front of it. The essential element of thermodynamic optimization is to coax a system (the horse) along the optimal path by interaction with a judicially varying reservoir (the moving carrot). This is called a horse-carrot process. If the distance from the horse to the carrot is small the horse will not move very quickly; if the distance is too large, it will give up and not move at all. The goal of optimization is to find the right driving force under the given conditions. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.