Thermodynamics, entropy and waterwheels

Franco Bagnoli

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arXiv · 1609.05090

Thermodynamics, entropy and waterwheels

Franco Bagnoli

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Abstract

In this paper the analogy between a thermal engine and a waterwheel is developed in details, showing that the analogous of the flow of water in an hydraulic engine is the flow of entropy in a thermal one. This analogy mat serve to analyse in details the aspects of a thermal engine that are quite distant from pupils' intuition. The discussion is complemented by an illustration of the working of thermal and hydraulic engines at the microscopic level, thus furnishing a view of what heat and work are at this level, and introducing the statistical and information aspects of entropy. Both hydraulic and thermal non-ideal engines are also discussed.

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Franco Bagnoli. 2016-09-15. Thermodynamics, entropy and waterwheels. https://arxiv.org/abs/1609.05090

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