Adrian Bejan I Carnot Efficiency Impossibility, from Design in Nature

In this video, Adrian Bejan explores the concept of Carnot efficiency and its status as an unattainable ideal in practical systems. He outlines the historical development of engines, beginning with the early steam engines and continuing with James Watt's innovations that enhanced efficiency. Bejan underscores the significance of grasping thermodynamic principles, especially the laws governing heat transfer, energy loss, and the unavoidable imperfections within engine systems. He clarifies that while Carnot’s theoretical efficiency represents the maximum possible, real engines face limitations due to material properties, heat escapes, and design obstacles that hinder reaching this ideal. Through practical examples, Bejan demonstrates how power is transmitted and lost across different systems, ranging from animal movement to large energy plants, emphasizing the inevitable losses attributed to thermal conductivity and structural constraints.

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Umit Gunes, Ph.D.
Assoc. Prof., Yildiz Technical University
umitgunes.com