William John Macquorn Rankine Early Life Thermodynamics

Born in Edinburgh to British Army lieutenant David Rankine and Barbara Grahame, Rankine was initially educated at home owing to his poor health. In 1836 Rankine began to study a spectrum of scientific topics at the University of Edinburgh, including natural history under Robert JamesonRobert Jameson ( 1774- 1854), Scottish naturalist and mineralogist, was born in Leith in July 1774. His early education was spent in Edinburgh, after which he became the apprentice of a surgeon in Leith, with the aim of going to sea. He also attended clas and natural philosophyNatural philosophy is a term applied to the objective study of nature and the physical universe before the development of modern science. In other words, all forms of science historically developed out of philosophy or more specifically natural philosophy under James ForbesJames David Forbes ( April 20, 1809 December 31, 1868) was a Scottish physicist who worked extensively on the conduction of heat, seismology and glaciology. Forbes was a resident of Edinburgh for his entire life, educated at the University and a professor, winning several scholastic awards and prizes. During vacations, he assisted his father who had become superintendent of the Edinburgh and Dalkeith RailwayThe Caledonian Railway was a Scottish Railway company which was grouped in to the London Midland and Scottish Railway by the Railways Act 1921 in 1923. Pre-grouping British railway companies External link .. He left Edinburgh in 1838Events January 6 Samuel Morse first publicly demonstrates the telegraph. January 8 Alfred Vail demonstrates a telegraph using dots and dashes (this is the forerunner of Morse code) January 12 Joseph Smith, Jr. and Sidney Rigdon flee Ohio for Missouri Marc without graduating, perhaps because of straitened family finances, and became apprenticed to Sir John Benjamin MacneillSir John Benjamin Macneill ( 1792/ 3 2 March 1880) was an eminent Irish civil engineer of the 19th century, closely associated with Thomas Telford. His most notable projects were railway schemes in Ireland and Northern Ireland he was born close to the pre, surveyor to the Irish Railway Commission . Even at this early stage of his career, he developed a technique ( Rankine's method ) for laying out circular curves, fully exploiting the theodoliteA theodolite (am. transit is an instrument for measuring both horizontal and vertical angles, as used in triangulation networks. It consists of a telescope mounted movably within two perpendicular axes, the horizontal or trunnion axis, and the vertical ax and making a substantial improvement in accuracy and productivity over existing methods.

The year 1842 also marked Rankine's first attempt to reduce the phenomena of heat to a mathematical form but he was frustrated by his lack of experimental data.

2 Thermodynamics

2.1 Work

In 1848, his interests turned to molecular physics at a time when the atomic hypothesis was still controversial and immature. Rankine attempted to apply his hypothesis of molecular vortices to the phenomena of birefringence (possibly motivated by the earlier work of Forbes) and of elasticity but without success.

Undaunted, he returned to his youthful fascination with the mechanics of the heat engine. Though his theory of circulating streams of elastic vortices whose volumes spontaneoulsy adapted to their environment sounds fanciful to scientists formed on a modern account, by 1849, he had succeeded in finding the relationship between saturated vapour pressure and temperature. The following year, he used his theory to establish relationships between the temperature, pressure and density of gases, and expressions for the latent heat of evaporation of a liquid. He accurately predicted the surprising fact that the apparent specific heat of saturated steam would be negative.

Enboldened by his sucess, he set out to calculate the efficiency of heat engines and used his theory as a basis to deduce the principle, enunciated by Sadi Carnot, that the maximum efficiency of a heat engine is a function only of the two temperatures between which it operates. Though a similar result had alredy been derived by Rudolf Clausius and William Thomson, 1st Baron Kelvin, the work marked the first step on Rankine's journey to develop a more complete theory of heat.

From 1853, Rankine recast the results of his molecular theories in terms of a macroscopic account of energy and its transformation. He distinguished between actual energy which was lost in dynamic processes and potential energy by which it was replaced. He assumed the sum of the two energies to be constant, an idea already familiar in the conservation of energy. From 1854, he made wide use of his thermodynamic function which he later realised was identical to entropy. By 1855, Rankine had formulated a science of energetics which gave an account of dynamics in terms of energy and transformation rather than force and motion. The theory was very influential in the 1890s.

Energetics offered Rankine an alternative, and rather more mainstream, approach, to his science and, from the mid 1850s, he made rather less use of his molecular vortices. However, as late as 1864, he contended that the microscopic theories of heat proposed by Clausius and James Clark Maxwell, based on linear atomic motion, were inadequate. It was only in 1869 that Rankine admitted the success of these rival theories. By that time, his own model of the atom had become almost identical with that of Thomson.

He used his own theories to develop a number of practical results and to elucidate their physical principles including:

The Rankine-Hugoniot equation for propagation of shock waves;
The Rankine cycle, an analysis of an ideal heat-engine with a condensor;
Properties of steam, gases and vapours.

He proposed the Rankine temperature scale in 1859.

2.2 Assessment

to be done

3 Other work

He served as professor of engineering at the University of Glasgow from 1855, pursuing engineering research along a number of lines in civil and mechanical engineering.

3.1 Civil engineering

Rankine made contributions to:

Forces in frame structures;
Soil mechanics;
Earth pressures, and the stability of retaining walls, especially the graphical Rankine method .

3.2 Naval architecture

Rankine body

to be done

4 Personal life

Rankine held the rank of Senior Major in the reservist Scottish Rifle Volunteers . He was an enthusiastic singer who composed his own songs.

He died in Glasgow, a bachelor.

5 Honours

Fellow of the Royal Society of Edinburgh, ( 1850);
Fellow of the Royal Society, ( 1853);
Keith Medal of the Royal Society of Edinburgh, ( 1854);
LL.D. from Trinity College, Dublin, ( 1857).

6 Important works

6.1 Books

Manual of Applied Mechanics, ( 1858);
Manual of the Steam Engine and Other Prime Movers, ( 1859);
Manual of Civil Engineering, ( 1861);
Machinery and Millwork, ( 1869).

6.2 Papers

Mechanical Action of Heat, ( 1850), read at the Royal Society of Edinburgh;
General Law of Transformation of Energy, ( 1853), read at the Glasgow Philosophical Society ;
On the Thermodynamic Theory of Waves of Finite Longitudinal Disturbance, ( 1869)

Rankine, William John Macquorn Rankine, William John Macquorn

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1 Early life