Second-law analysis: approaches and implications

Abstract

A comparison is presented of the main approaches to second‐law analysis (SLA) reported in the literature. Five SLAs are considered: exergy, physical‐exergy, exergy‐consumption, negentropy and entropy analyses. The application of the SLAs is illustrated through an example. In addition, several significant implications of SLA are examined in the fields of environmental impact and economics. The presentation herein of the approaches to and implications of SLA is expected to enhance understanding of SLA and improve its usefulness. Copyright © 1999 John Wiley & Sons, Ltd.

Flash cycle optimization of Sabalan geothermal power plant employing exergy concept

“…For a stream of fluid, the total exergy flow (E total ) can be expressed as: Both E KE and E PE are associated with high-grade energy and are fully convertible to work while E PH and E O are low-grade energy, for which the stream has to undergo physical and chemical processes while interacting with the environment. In this study, only physical exergy was considered since the process involves only fixed-composition flows (Rosen, 1999). Therefore, the exergy is expressed as the maximum work when the stream of a substance is brought from its initial state to the environmental state defined by P 0 and T 0 by physical processes involving only thermal interaction with the environment (Kotas, 1995).…”

Heat transfer in a large triangular-roof enclosure based on the second law analysis

“…Primarily studies of entropy generation obtained by Bejan [1,2]. Also, fundamentals of entropy generation presented by San et al [3], Rosen [4] and Nurusawa [5]. The optimal design criteria for thermal systems by minimizing their entropy generation have been a topic of great interest.…”

Application of the exergy method to the environmental impact estimation: The nitric acid production as a case study

“…There are many difficulties, ensuing from the fact, that the thermodynamic environment is not identical to the real environment, which is much more complex and multiform. Many authors propose various approaches, concerning different aspects of the environment and exergy nexus: Ayres [9], Rosen [10], Valero and Botero [11], Cornelissen [12], Gong and Wall [13], etc.…”