From Lotka to the entropy generation approach

• Lotka’s approach is analyzed.
• Irreversibility is the fundamental quantity for the analysis of the open systems.
• The entropy generation describes the irreversibility of the open systems.
• A link between Lotka’s approach and entropy generation is done.

The entropy approach to the evolution of open systems is analyzed, using Lotka’s principle as a starting point. A Lagrangian is sought after to develop an analytical method for the evaluation of the stationary states of open irreversible systems. The stationary conditions for open systems are first obtained on the basis of the entropy generation and its maximum principle, suggesting them as a link between the classical engineering thermodynamics approach and the more mathematical Lotka point of view.