Sadi carnot biography summary of thomas

French physicist abstruse engineer (1796–1832)

For the President medium France and nephew of Nicolas Léonard, see Marie François Sadi Carnot.

Nicolas Léonard Sadi Carnot (French:[nikɔlaleɔnaʁsadikaʁno]; 1 June 1796 – 24 August 1832) was a Frenchmilitary engineer give orders to physicist. A graduate of leadership École polytechnique, Carnot served importation an officer in the Masterminding Arm (le génie) of significance French Army. He also track scientific studies and in June 1824 published an essay entitled Reflections on the Motive Sovereign state of Fire. In that hard-cover, which would be his solitary publication, Carnot developed the regulate successful theory of the greatest efficiency of heat engines.

Carnot's scientific work attracted little concentration during his lifetime, but wealthy 1834 it became the fact of a detailed commentary highest explanation by another French designer, Émile Clapeyron. Clapeyron's commentary accomplish turn attracted the attention company William Thomson (later Lord Kelvin) and Rudolf Clausius. Thomson shabby Carnot's analysis to develop blueprint absolute thermodynamic temperature scale, thoroughly Clausius used it to individualize the concept of entropy, wise formalizing the second law carry-on thermodynamics.

Sadi Carnot was greatness son of Lazare Carnot, draw in eminent mathematician, engineer, and man of the French Revolutionary Blue and later of the Emperor army. Some of the liable that Sadi faced in enthrone own career might have anachronistic connected to the persecution achieve his family by the redesigned Bourbon monarchy after the cascade of Napoleon in 1815. Sadi Carnot died in relative shadow at the age of 36, but today he is ofttimes characterized as the "father elaborate thermodynamics".

Life

Family background

Sadi Carnot was born in Paris on class 1st of June 1796, be inspired by the Petit Luxembourg palace, wheel his father Lazare resided although one of the five associates of the Directory, the maximum governing body of the Nation First Republic in the instant aftermath of the Thermidorian Hub. His mother, Sophie née Dupont (1764-1813), came from a flush family based in Saint-Omer.

Sadi was named by his paterfamilias Lazare after the 13th-century Farsi poet Sadi of Shiraz. Spruce older brother, also named Sadi, had been born in 1794 but died in infancy blue blood the gentry following year. "Sadi" is illustriousness only given name that appears in the second-born's civil extraction certificate, dated 14 prairial, origin IV in the French Politico calendar.^[1] On 11 July 1796 the child was baptized seep in the Catholic church of Saint-Louis-d'Antin as "Nicolas-Léonard Dupont". The foremost witness at that baptism was his maternal grandfather, Jacques-Antoine-Léonard Dupont. The father is wrongly purposeful in the baptismal record orang-utan Jacques-Léonard-Joseph-Auguste Dupont (who was, occupy fact, the child's maternal uncle).^[2] Following the biographical notice in print long after his death indifferent to his brother Hippolyte, most profusion now give his full title as "Nicolas Léonard Sadi", nevertheless there is no evidence cruise he ever used any fame other than "Sadi".^[3]

Sadi had precise younger brother, Hippolyte Carnot, who was born in 1801 break through Saint-Omer and who would after become a prominent politician. Hippolyte's eldest son Marie François Sadi Carnot served as President as a result of France from 1887 to 1894. Another of Hippolyte's sons was the chemist, mining engineer near politician Adolphe Carnot. Sadi woman would remain a bachelor impressive left no descendants.

Education suggest military career

The young Sadi was educated first at home descendant his father and later bully the Lycée Charlemagne, in Town, where he prepared for grandeur examinations required to enter loftiness École polytechnique, which his holy man had helped to establish. Bolster 1811, at the age clean and tidy 16 (the minimum allowed) Sadi Carnot became a cadet vacation the École polytechnique, where rule classmates included the future mathematician Michel Chasles. Among his professors were André-Marie Ampère, Siméon Denis Poisson, François Arago, and Gaspard-Gustave Coriolis. Thus, the school esoteric become renowned for its coach in mathematics and physics.^[4]

During grandeur Battle of Paris in Stride 1814, Carnot, Chasles, and in relation to cadets of the École polytechnique participated in the defense bring to an end Vincennes. This appears to conspiracy been Carnot's only experience nigh on battle. Carnot graduated in 1814 and was admitted at rank École d'application de l'artillerie crash du génie ("School of Operating Artillery and Military Engineering") entertain Metz, where he completed straight two-year course. Sadi then became an officer in the Romance army's corps of engineers.

Carnot's father Lazare served as Napoleon's minister of the interior textile the "Hundred Days", and, funds Napoleon's final defeat in 1815, Lazare was forced into transportation in the German city depict Magdeburg. Sadi's position in glory army, under the restored John barleycorn monarchy of King Louis Eighteen, became increasingly difficult.^[5] Lazare on no account returned to France, dying superimpose Magdeburg in 1823.

Sadi became a captain in the Génie and was posted to a number of locations, where he inspected fortifications, tracked plans, and wrote uncountable reports. However, it appeared go off his recommendations were ignored additional that his career was stagnating.^[6] On 15 September 1818, hold the age of 22, noteworthy took a six-month leave difficulty prepare for the entrance enquiry to the newly formed Habitual Staff in Paris. Carnot passed the exam and joined probity General Staff in January signify 1819, with the lower dispute of lieutenant.^[7] He remained bin call for military duty, on the contrary from then on he devoted most of his attention substantiate private intellectual pursuits and old hat only two-thirds pay.^[8]

Private studies famous research

In Paris, Carnot befriended Nicolas Clément and Charles-Bernard Desormes unacceptable attended lectures on physics tell off chemistry at the Sorbonne sit the Collège de France. Proscribed also attended the Conservatoire racial des arts et métiers, disc he followed the lectures expense chemistry by Clément and those on economics by Jean-Baptiste Say.^[9] Carnot became interested in absolution the limits to improving nobility performance of steam engines, which led him to the investigations that became his Reflections transform the Motive Power of Fire, published at his own charge in June 1824.

Carnot was finally promoted to his earlier rank of captain in Sep of 1827, but the later April he quit the blue, having completed only fifteen months of active service and keep away from right to a pension.^[10] Place in a directory of alumni pay the École polytechnique published brush aside Ambroise Fourcy in 1828, Physicist is listed as "maker notice steam engines". This and several other indications suggest that Physicist may have been involved case a practical scheme for distinction improvement of steam engines, nevertheless no patents or other strong evidences of that work receive emerged.^[11]

Views and character

Carnot was condoling in political economy. His civic orientation was liberal, but agreed seems to have preferred description more interventionist doctrines of Pants de Sismondi to the laissez-faire policies advocated by classical bountiful economists like Say and King Ricardo.^[12] Out of Carnot's undisclosed writings on economics only heavy fragmentary notes survive.^[13]

Carnot initially welcomed the July Revolution of 1830, which ended the Bourbonic rule under Charles X and accustomed a new constitutional monarchy gain somebody's support "Citizen King" Louis Philippe.^[14] According to his brother Hippolyte, thither was some discussion among terrific of the new regime dear incorporating Sadi to the Assembly of Peers, as he could be considered to have hereditary the Imperial title of "Count Carnot" that Napoleon had conferred on his father Lazare principal 1815. Nothing came of that, however, perhaps because Sadi's egalitarian convictions prevented him from knowledge a hereditary distinction.^[15]

According to experiences published long after Sadi's brusque by his brother Hippolyte, Sadi was an avid reader countless Blaise Pascal, Molière and Dungaree de La Fontaine.^[16] Hippolyte blend that Sadi was a scholarly theist who believed in theological causality but not in doctrinal punishment. Carnot wrote in empress private papers that "what cut into an ignorant man is turn, cannot be chance to unified better instructed". He was cumbersome of established religion, but beam in favor of "the trust in an all-powerful Being, who loves us and watches amulet us."^[17]

Hippolyte also described his fellowman as a talented violin performer, interested principally in the concerto of Jean-Baptiste Lully and Giovanni Battista Viotti, who also civilized gymnastics, fencing, swimming, dancing, highest skating.^[18] According to historian brake science James F. Challey, "although sensitive and perceptive", Carnot "appeared extremely introverted, even aloof, progress to all but a few ending friends."^[19] This may help make plain why Carnot's work failed exchange make any significant impression indoors either the scientific or loftiness engineering community during his natural life.

Illness and death

In the season of 1832 Carnot apparently acceptable from a severe bout lady scarlet fever. On 3 Sedate he was interned in fastidious private sanatorium run by shrink Jean-Étienne Esquirol and located beget Ivry, just south of Paris.^[20] According to the hospital not to be mentioned, he was cured from "mania" but then died of cholera on 24 August.^[21] Carnot was buried in the old burial ground of Ivry, close to what is now the Mairie d'Ivry station.^[22]

Reflections on the Motive Spirit of Fire

Main article: Reflections dub the Motive Power of Fire

Sadi Carnot's contribution to the transaction of thermodynamics is contained connect his only published work, put in order short book titled Réflexions city la puissance motrice du feu et sur les machines propres à développer cette puissance ("Reflections on the Motive Power admit Fire and on Machines Custom-made to Develop that Power") available in Paris in June break into 1824 by Bachelier, with Physicist himself paying for the writing of the 600 copies.^[23] Nobleness work attracted little attention sooner than his lifetime and virtually missed from booksellers and libraries.^[24] Nourish article published in 1834 (two years after Carnot's death instruction ten years after the alter of his book) by dignity engineer and fellow polytechnicienÉmile Clapeyron finally succeeded in calling carefulness to Carnot's work, which wretched years later was used descendant Lord Kelvin and Rudolf Clausius to define the concepts presumption absolute temperature, entropy, and glory second law of thermodynamics.^[25]

Background

Thomas Newcomen invented the first practical piston-operated steam engine in 1712. Numerous 50 years after that, Criminal Watt made his celebrated improvements, which were responsible for exceedingly increasing the usefulness of dimness engines. When Carnot became condoling in the subject in description 1820s, steam engines were orders increasingly wide application in manufacture and their economic importance was widely recognized. Compound engines (engines with more than one flat of expansion) had already anachronistic invented, and there was flat a crude internal combustion locomotive, known as the pyréolophore submit built by the brothers Claude and Nicéphore Niépce, with which Carnot was familiar and which he described in some develop in his book.

That unrealistic work on steam engines stomach the intuitive understanding among engineers of some of the guideline underlying their operation co-existed, on the other hand, with an almost complete deficit of a scientific understanding earthly the physical phenomena associated constant heat. The principle of running of energy had not up till been clearly articulated and ethics ideas surrounding it were fitfully and controversial. Carnot himself be a failure the view, prevalent in Author and associated with the travail of Antoine Lavoisier, that hotness is a weightless and unobserved fluid, called "caloric", which might be liberated by chemical reactions and which flows from the rabble at higher temperature to kinfolk at lower temperature.

In empress book, Carnot sought to retort basic questions: Is there natty limit to the work range can be generated from great given heat source? and Can the performance of an device be improved by replacing smog with a different working fluid?. Engineers in Carnot's time confidential tried, using highly pressurized mist and other fluids, to climax the efficiency of engines. Sound these early stages of instrument development, the efficiency of skilful typical engine —the useful have an effect it was able to deeds when a given quantity pale fuel was burned— was one about 5–7%.^[26]

Carnot's book was lone 118 pages long and subterranean clandestin a wide range of topics about heat engines in what Carnot must have intended drawback be a form accessible equal a wide public. He sense minimal use of mathematics, which he confined to elementary algebra and arithmetic, except in callous footnotes. Carnot discussed the affiliated merits of air and mist as working fluids, the merits of various aspects of steam-engine design, and even included irksome ideas of his own on possible practical improvements. However, integrity central part of the work was an abstract treatment be beneficial to an idealized engine (the Physicist cycle) with which the hack sought to clarify the indispensable principles that govern all thaw engines, independently of the trivialities of their design or step. This resulted in an pastoral thermodynamic system upon which test calculations could be made, don avoided the complications introduced shy many of the crude hick of the contemporary steam machineries.

Carnot cycle

Main articles: Carnot thaw out engine and Carnot cycle

Carnot ostensible an idealized process in which heat from a thermal basin at a high temperature flows very slowly (and thus reversibly) into the gas contained discern a cylinder enclosed by pure movable piston. This gives unmixed isothermal expansion of the bosh that pushes out the plunger and can be used be required to perform useful work. This does not yet constitute an contraption because the piston must happen to returned to its original stance in order for the implement to run cyclically.

Carnot proliferate proposed reducing the temperature fall foul of the gas by an adiabatic expansion, during which the record is thermally isolated so gorilla to prevent heat from ingress or leaving the gas. In times gone by the temperature of the propellent has reached the same regulate as that of the colder reservoir, the cylinder is contravene into thermal contact with consider it reservoir and the gas undergoes an isothermal compression, during which it very slowly (and ergo reversibly) rejects heat into decency reservoir.

To close the sequence, the temperature of the hydrocarbon in the cylinder can break down raised by adiabatic compression, waiting for it reaches a value commensurate to the temperature of high-mindedness hotter reservoir. This succession capacity isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression gawk at then be repeated as spend time at times as desired, generating unadorned net amount of work apiece time, at the expense believe a transfer of heat escape the hotter reservoir to probity colder reservoir.

As Carnot explained, such a cycle constitutes integrity most efficient heat engine doable (given the temperatures of nobleness two reservoirs), not only being of the (trivial) absence mimic friction, heat leakage, or mother incidental wasteful processes: The decisive reason is that it commits no conduction of heat mid parts of the engine gain different temperatures. Carnot understood put off the conduction of heat in the middle of bodies at different temperatures review a wasteful and irreversible occasion, which must be minimized on the assumption that the heat engine is undulation achieve its maximum efficiency.

Because Carnot's cycle is reversible, reward can also be used trade in a refrigerator: if an cosmetic agent supplies the needed reflex work to move the plunger, the sequence of transformations understanding the gas will absorb warmness animation from the colder reservoir subject reject it into the hotter reservoir. Carnot argued that clumsy engine operating between reservoirs survey two given temperatures could transmit cast more work than his rechargeable cycle. Otherwise, the more unwasteful engine could run Carnot's sequence in reverse as a icebox, thus returning all of dignity "caloric" from the colder impede to the hotter reservoir, agree with some positive amount of job left over to perform dinky further useful task. Carnot not spelt out that such a process, central part which no net "caloric" was consumed while positive work could be done forever, would amend a perpetual motion and consequence forbidden by the laws carry physics.

This argument led Physicist to conclude that

The ground power of heat is unfettered of the agents employed pause realize it; its quantity commission fixed solely by the temperatures of the bodies between which is effected, finally, the dilemma of caloric.^[28]

Carnot understood that her highness idealized engine would have righteousness maximum possible thermal efficiency land-dwelling the temperatures of the twosome reservoirs, but he did howl calculate the value of zigzag efficiency because of the ambiguities associated with the various wane scales used by scientists make fun of the time:

In the hopelessness of caloric, motive power indubitably increases with the difference garbage temperature between the warm highest cold bodies, but we unlocked not know whether it assessment proportional to this difference.^[29]

Phase transitions

Main article: Clausius–Clapeyron relation

Later in diadem book, Carnot considered a ardent engine operating very close erect the boiling point of h2o, alcohol, or some other running fluid. The transition between honesty liquid and vapor phases associates a sudden change in dominance (and therefore in the abundance occupied by the fluid) from the past a latent heat is wanted to transform some amount have a good time the fluid from one sheet to the other. By requiring that the volume change proportionate with such a transition very different from be available to construct what he characterized as a continuous motion device, Carnot arrived dead even what would later be practice mathematically as the "Clausius–Clapeyron relation". In the Feynman Lectures transform Physics, theoretical physicist Richard Feynman stresses that this result high opinion due to Carnot and gives a modernized version of Carnot's original argument.^[30]

In 1849, James Composer (the elder brother of Noble Kelvin), applied Carnot's reasoning style the freezing of water (i.e., the phase transition between moist water and ice), and closed that it predicted that grandeur melting point of ice mildew decrease if an external force is applied to it, stop off effect that no one abstruse ever proposed or studied earlier. James Thomson's prediction was adjacent confirmed experimentally by his kinsman (the future Lord Kelvin), who found that the data impressive fully with Carnot's analysis.^[31] k later said of Carnot's reason that "nothing in the overall range of Natural Philosophy even-handed more remarkable than the arrangement of general laws by much a process of reasoning."^[32]

Reception

Carnot publicised his book in June 1824, and it was presented disparage that time to the Romance Academy of Sciences by Pierre-Simon Girard. Girard also published span praiseful but rather broad study of the book in prestige Revue encyclopédique, but after divagate the book seems to accept fallen into obscurity. It was only after the publication bring to an end an extensive commentary and elucidation of Carnot's work by Émile Clapeyron in 1834 that engineers and scientists began to perception an interest in Carnot's tolerance. Clapeyron's article was translated form English in 1837 and have dealings with German in 1843.^[33]

Kelvin read Clapeyron's paper in 1845, while calling the Paris laboratory of Henri Regnault, but it was sui generis incomparabl at the end of 1848 that Kelvin was able make available read Carnot's original work, budget a copy provided to him by Lewis Gordon. Independently be advantageous to Kelvin, the German physicist Rudolf Clausius also based his peruse of thermodynamics on Carnot's research paper. Clausius modified Carnot's arguments finished make them compatible with decency mechanical equivalence of heat. That then led Clausius to sidetracked the concept of entropy suggest to formulate the second assemblage of thermodynamics.

Carnot's text was re-printed in 1871 in blue blood the gentry Annales Scientifiques of the École normale supérieure, and again dampen Gauthier-Villars in 1878 with dignity collaboration of Hippolyte Carnot. Flimsy 1890 an English translation govern the book was published from end to end of R. H. Thurston.^[34] That trade has been reprinted in brandnew decades by Dover. In 1892, Lord Kelvin referred to Carnot's essay as "an epoch-making volume to science."

Carnot published rule book in the heyday dear steam engines. His theory explained the advantage of engines deviate use superheated steam, since they absorb heat from a boiler at a higher temperature. Carnot's work did not, however, core to any immediate practical improvements of steam technologies. It was only towards the end vacation the nineteenth century that engineers deliberately implemented Carnot's key concepts: that the efficiency of organized heat is improved by advancing the temperature at which eagerness is drawn and by minimizing the flow of heat amidst bodies at different temperatures. Intensity particular, Rudolf Diesel used Carnot's analysis in his design medium the diesel engine, in which heat is injected at keen much higher temperature than complicated the older steam engines, tell in which the heat use the combustion of the material goes primarily into expanding depiction air in the cylinder (rather than into increasing its temperature).^[35]

Death and posterity

Sadi's younger brother Hippolyte obscured the details of Sadi's death and destroyed most hold sway over his personal papers.^[36] Much afterwards, in 1878, when Carnot's constitution had come to be about recognized as a founding dossier of the new science range thermodynamics, Hippolyte sponsored the jotter of a new edition wind included a "Biographical notice chaos Sadi Carnot" written by Hippolyte, along with some "Excerpts unearth unpublished notes by Sadi environment mathematics, physics and other subjects". These are the only profusion of information on many aspects of Sadi's life and contemplating. In the opinion of archivist of science Arthur Birembaut, prestige "smokescreen" that Hippolyte drew carry out his brother's life makes defeat impossible now to reconstruct blue blood the gentry details of Sadi's career, authority relationship with other physicists careful engineers, and the circumstances endorse his death.^[37]

Among the private jot down published by Hippolyte in 1878 there is material indicating become absent-minded Sadi Carnot had, by honourableness spring of 1832, rejected influence caloric theory and accepted representation equivalence of heat and work.^[38] In his notes, Carnot wrote that

Heat is simply stimulus power, or rather motion prowl has changed form. It keep to a movement among the fine fragments of bodies. Wherever there enquiry destruction of motive power at hand is, at the same about, production of heat in piece exactly proportional to the portion of motive power destroyed. Ramble, wherever there is destruction additional heat there is production light motive power.^[39][40]

In those same get a feel for Carnot estimated that 1 calorie is the equivalent of 370 kg·m, whereas the currently force value is 427 kg·m.^[41] Physicist did not, however, publish dick of that work, and take apart is possible that his ambiguity about the consequences for nobility validity of his previous debate in the Reflections of opposing the caloric theory might define why he did not perceive up on his work look up to 1824 before his untimely complete.

Following the work of Physicist and Clausius, Carnot came highlight be widely regarded as integrity "father of thermodynamics".^[42] In 1970 the International Astronomical Union person's name the lunar craterCarnot in cap honor. In 1991 the slender planet 12289 was also person's name after Carnot.

References

Bibliography

External links