Nicolas Carnot was born on June 1, 1796 in Paris, France. He was the son of Lazare Nicolas Marguerite Carnot. When Sadi was born his father was a member of the Directory, which was the French Revolutionary government. Sadi was brought up in a rough evironment of clashing politics and sciences. His father retired from his position as napoleon's minister in order to devote his time to educating his two sons. At the age of 16 Sadi was sent to Lycee Charlemagne in Paris in order to prepare him for the testings to get into Ecole Polytechnique. At this young age of 16 he entered the Ecole Polytechnique, two years later at the age of 18 he graduated from there. After this he took a two year course in military engineering.
Some years later Sadi went to visit his father since he was exiled after the defeat of Napoleon. During his visit of his father they spoke in great detail of a steam engine that had come through where his father lived. This filled Sadi with great excitement as he had plan to develop a theory for steam engines. Once he returned to Paris he began immediatley working on the mathematical theory of heat. This lead to the start of the modern theory of what we know today as thermodynamics. Sadi's first piece that he worked on was a mathematical expression for the work done by one kilogram of steam. This research done my Sadi was never published to the public. It wasn't until later that Sadi finally published something on his works.
When his father died his brother, Hippolyte Carnot came to Paris in order to help his brother finish his book on steam engines that he was currently working on. Sadi's book was finally published in 1824, and in his book was the theory of the "Carnot Cycle"
In 1827 he was called back into the military to work as a military engineer which he did for less than one year. He quickly retired and moved back to Paris to continue his work on the theory of heat. In 1832 Sadi Carnot became very sick with the cholera epidemic and he died one day after getting cholera, at the young age of only 36. Carnot is known as the father of thermodynamics. He was the first person to show the relationship between work and heat.
Carnot Cycle
With the Carnot Cycle, Carnot was able to show that a heat engine which operated at an ideal, reversible cycle, that was between two energy reservoirs was the most efficient engine possible. Although this is physically not a real engine that can be built, it's ideally the most efficient engine there is and no engine can ever be made more efficient.
- - 2) This is an isothermal process (constant temperature) in which the gas expands while it is in contact with the hot reservoir
- - 3) This is an adiabatic process (no energy) in which the gas expands
- - 4) This is an isothermal process in which the gas is compressed while it is in contact with the cold reservoir
- - 1) This is an adiabatic process in which the gas is compressed
Carnot Engine
- "Air at temperature T1 is held in a cylinder, closed by an insulated piston (starting position: cd). A hot source A, with temperature T1, and a cold source B, with temperature T2, constitute infinite reservoirs of heat.
- The cylinder is put in contact with A: the heat passes from the source to the air, that relaxes freely and pushes the piston to the position ef.
- The cylinder is isolated from all source of heat. During its adiabatic expansion, the air pushes the piston until gh: its temperature falls to T2.
- The cylinder, with temperature T2 then, is put in contact with the heat source B, with identical temperature. A "theoretical" experimenter pushes the piston downwards: this isothermal compression brings it to position cd. Heat passes from the air to the source B.
- The cylinder is isolated from the outside again. The "theoretical" experimenter continues to push the piston until it reaches position ik, in such a way that the air temperature reaches T1.
- The cylinder is put in contact with A, which delivers heat to the air: it expands until the piston comes back to its initial position cd."
