热机简史：早期蒸汽机应用 Q矿业，尤其是采煤 Q治金：粉碎机以及鼓风机 Q纺织业：抽水驱动水力机直接驱动 Q交通运输业：蒸汽火车、轮船 "To take away today from England her steam-engines would be to take away at the same time her coal and iron.It would be to dry up all her sources of wealth,to ruin all on which her prosperity depends,in short,to annihilate that colossal power. The destruction of her navy,which she considers her strongest defence,would perhaps be less fatal." -Carnot,"Reflections on the Motive Power of Fire and on Machines Fitted to Develop that Power
热机简史：早期蒸汽机应用 矿业，尤其是采煤 冶金：粉碎机以及鼓风机 纺织业：抽水驱动水力机 ☞ 直接驱动 交通运输业：蒸汽火车、轮船 “To take away today from England her steam-engines would be to take away at the same time her coal and iron. It would be to dry up all her sources of wealth, to ruin all on which her prosperity depends, in short, to annihilate that colossal power. The destruction of her navy, which she considers her strongest defence, would perhaps be less fatal.” —– Carnot, “Reflections on the Motive Power of Fire and on Machines Fitted to Develop that Power
2.4 Carnot定理 Carnot理想热机 "Reflections on the Motive Power of Fire and on Machines Fitted to Develop that Power",Sadi Carnot (1824) Q主要目的：提高热机效率 如何提高热机效率效率，热机效率是否有上限？ Q普适的热机理论：对热机工作提供一个完整的理论认识 (steam-engines')theory is very little understood,and the attempts to improve them are still directed almost by chance....The phenomenon of the production of motion by heat has not been considered from a sufficiently general point of view....Machines which do not receive their motion from heat...can be studied even to their smallest details by the mechanical theory.All cases are foreseen,all imaginable movements are referred to these general principles,firmly established,and applicable under all circumstances.This is the character of a complete theory.A similar theory is evidently needed for heat-engines
2.4 Carnot 定理 Carnot 理想热机 “Reflections on the Motive Power of Fire and on Machines Fitted to Develop that Power”, Sadi Carnot (1824) 主要目的：提高热机效率 如何提高热机效率效率，热机效率是否有上限？ 普适的热机理论：对热机工作提供一个完整的理论认识 · · · (steam-engines’) theory is very little understood, and the attempts to improve them are still directed almost by chance. · · · The phenomenon of the production of motion by heat has not been considered from a sufficiently general point of view. · · · Machines which do not receive their motion from heat · · · can be studied even to their smallest details by the mechanical theory. All cases are foreseen, all imaginable movements are referred to these general principles, firmly established, and applicable under all circumstances. This is the character of a complete theory. A similar theory is evidently needed for heat-engines. · · ·
Carnot的主要贡献 Q普适的热机理论 In order to consider in the most general way the principle of the production of motion by heat,it must be considered independently of any mechanism or any particular agent.It is necessary to establish principles applicable not only to steam-engines but to all imaginable heat-engines,whatever the working substance and whatever the method by which it is operated. 0. 超越热机理论：普适的热理论 We shall have it (the theory of heat-engines)only when the laws of physics shall be extended enough,generalized enough,to make known beforehand all the effects of heat acting in a determined manner on any body. 0 Carnot对热力学的贡献 系统状态，准静态过程，循环，可逆过程/不可逆过程
Carnot 的主要贡献 普适的热机理论 In order to consider in the most general way the principle of the production of motion by heat, it must be considered independently of any mechanism or any particular agent. It is necessary to establish principles applicable not only to steam-engines but to all imaginable heat-engines, whatever the working substance and whatever the method by which it is operated. 超越热机理论：普适的热理论 We shall have it (the theory of heat-engines) only when the laws of physics shall be extended enough, generalized enough, to make known beforehand all the effects of heat acting in a determined manner on any body. Carnot 对热力学的贡献 系统状态，准静态过程，循环，可逆过程/不可逆过程
Nicolas Leonard Sadi Carnot (6/1/1896-8/24/1832 o.Son of Lazare Carnot Lazare Nicolas Marguerite,Count Carnot,法国政治家、军事家、工程 师和数学家，代表作“Fundamen- tal Principles of Equilibrium and Movement'”基于机械能守恒讨论 机器效率一永动机是不可能的 o 1812,a student of Ecole Polytechnique in Paris o 1824,"Reflections on the Motive Power of Fire"118-page self-publicati sold for 3 francs Q1832,因霍乱而死 o 1834,Emile Clapeyron,"Memoir on the Motive Power of Heat o 1849,William Thomson,"An Account of Carnot's Theory of the Motive Power of Heat
Nicolas Léonard Sadi Carnot (6/1/1896—–8/24/1832) Son of Lazare Carnot Lazare Nicolas Marguerite, Count Carnot，法国政治家、军事家、工程 师和数学家，代表作 “Fundamental Principles of Equilibrium and Movement” 基于机械能守恒讨论 机器效率 ⇒ 永动机是不可能的 1812, a student of École Polytechnique in Paris 1824, “Reflections on the Motive Power of Fire ” 118-page self-publication, sold for 3 francs 1832, 因霍乱而死 1834，Émile Clapeyron, “Memoir on the Motive Power of Heat ” 1849, William Thomson, “An Account of Carnot’s Theory of the Motive Power of Heat
Sadi Carnot的热机和Lazare Carnot的水力机 Carnot把热机和水力机直接对比，认为和水力机类似，热机做功 的动力来自与Caloric从高温流到低温，由此分析热机效率。 。水力机两个不同的高度台热机需要两个不同的温度 。液体（水台热/Caloric)总是从高处往低处流 Q液体（水一热/Caloric)从高处往低处流时做功 。工作前后水的总量守恒，水的高度改变做功 台热守恒，流入热机的热=流出热机的热， 热的温度改变做功 Q液体流失降低效率一热的流失降低效率 霉理想热机不应该有无用的热损耗 霉工作物质吸热台体积变化一做功 霉不导致体积变化的热传导无用 露理想热机里不同温度的物体之间无直接热接触 Q水剧烈流动会损失能量一理想热机工作过程应该平缓 理想热机工作过程应该是可逆的准静态过程 a.Carnot循环
Sadi Carnot 的热机和 Lazare Carnot 的水力机 Carnot 把热机和水力机直接对比，认为和水力机类似，热机做功 的动力来自与 Caloric 从高温流到低温，由此分析热机效率。 水力机两个不同的高度 ⇔ 热机需要两个不同的温度 液体（水 ⇔ 热/Caloric）总是从高处往低处流 液体（水 ⇔ 热/Caloric）从高处往低处流时做功 工作前后水的总量守恒，水的高度改变做功 ⇔ 热守恒，流入热机的热 = 流出热机的热， 热的温度改变做功 液体流失降低效率 ⇔ 热的流失降低效率 ☞ 理想热机不应该有无用的热损耗 ☞ 工作物质吸热 ⇒ 体积变化 ⇒ 做功 ☞ 不导致体积变化的热传导无用 ☞ 理想热机里不同温度的物体之间无直接热接触 水剧烈流动会损失能量 ⇔ 理想热机工作过程应该平缓 ☞ 理想热机工作过程应该是可逆的准静态过程 Carnot 循环