Original scientific paper

Thermodynamic Basis of Thermo-Chemical Energy Systems and Fuel Cells

Stanislaw Sieniutycz ; Faculty of Chemical & Process Engineering, Warsaw University of Technology, 1 Waryńskiego Street, Warsaw, Poland

Abstract

This research treats power optimization for energy converters, such as thermal, solar and electrochemical engines (fuel cells). A common methodology is developed for the assessment of power limits in thermal systems and fuel cells. Thermodynamic analyses lead to converter efficiency and limiting power. Steady and dynamic systems are investigated. Static optimization of steady systems applies the differential calculus or Lagrange multipliers, dynamic optimization of unsteady systems uses variational calculus and dynamic programming. The primary result of the first is the limiting value of power, whereas that of the second is a total generalized work potential. The generalizing quantity depends on the thermal coordinates and a dissipation index, h, i.e. the Hamiltonian of the problem of minimum entropy production. The advanced thermodynamics, of an irreversible nature, implies stronger bounds on work delivered or supplied than the classical reversible work. It is shown how various analytical developments can efficiently be synthesized to quantitatively evaluate power limits in thermal systems and fuel cells of a simple topology (without countercurrent flows).

Keywords

Power generators; Chemical reactions; Efficiency; Fuel cells; Power limits

Hrčak ID:

107266

URI

https://hrcak.srce.hr/107266

Publication date:

4.2.2013.

Article data in other languages: croatian

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