Parsons, Charles Algernon (1854–1931)

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PARSONS, CHARLES ALGERNON (1854–1931)

Charles Algernon Parsons was born in London on June 13, 1854, the son of a wealthy, aristocratic Anglo-Irish family that was scientifically very distinguished. His father, William Parsons (third Earl of Rosse), a member of parliament, was an engineer, astronomer, and telescope-maker who had built the largest telescope in the world. His mother, Mary Countess of Rosse, best remembered as a photographer, was adept at architectural design and cast-iron foundry work.

The greater part of Parsons' childhood was spent at the family's castle and estate at Parsonstown (now Birr), County Offaly, Ireland. The workshops there were extensive, and he grew up surrounded by tools and machinery. He was privately educated by, among others, Sir Robert Ball, a man who encouraged him to spend time not just in the classroom, but also in the workshops. With these facilities and the guidance of his parents and tutor, he developed an exceptional talent for engineering.

The key to Parsons' success lies in the nature of his early training in science and engineering. In a letter concerning the design of yachts, he wrote that "they seem to design by rule of thumb in England—they should rely on model experiments, which would put them right." This is illustrative of an approach to engineering that was highly practical. He solved problems by building experiments and then meticulously observing and analyzing the results. It was an aspect of his character that was formed by the time he left Birr for his university education.

In July 1871, Parsons entered Trinity College Dublin, where he studied mathematics. In 1873, he entered St. John's College Cambridge and took his B.A. degree in mathematics in 1877. Thus, at the age of 23 he graduated from the university armed with a battery of practical and theoretical skills that allowed him to gain unique insights into the engineering problems of the time.

Having spent five years at the university honing his theoretical skills, Parsons then returned to the practical by entering the engineering firm of W. G. Armstrong & Co. in Newcastle-upon-Tyne. As a premium apprentice he was allowed to spend some of his time constructing his own experiments, provided that he paid the material and labor costs himself. Using this time, he developed a high-speed, four-cylinder epicycloidal steam engine.

The Armstrong company was not interested in producing the engine; therefore in 1881, Parsons moved to Kitson's of Leeds who took it into production. At Kitson's he occupied himself with experiments in rocket powered torpedoes that, although unsuccessful, provided useful background for his next project, the steam turbine.

Parsons left Kitson's and joined Clarke, Chapman & Co. of Gateshead as a junior partner. This was the turning point in his career, his previous working life having been devoted to learning and developing his skills. In 1884, he decided "to attack the problem of the steam turbine and of a very high speed dynamo." During the next ten years of his life, he made huge strides in the construction of dynamos and steam turbines.

In the late 1880s the Industrial Revolution was demanding ever-increasing amounts of energy. Electrical power was an obvious solution to this demand; however, it was not yet possible to generate very high power. Parsons realized that high-speed dynamos were the answer, and that the best source of rotational energy would be a steam turbine, whose nonreciprocating nature makes it capable of far higher speeds than conventional reciprocating engines.

Turbine designers had been experimenting with machines in which the blades were driven by a high-velocity steam jet that expanded through them in a single stage. It had been shown that steam-jet velocities of the order of 1000 m/s were required.

For a steam turbine to work efficiently, it is necessary that the velocity of the tips of the turbine blades be proportional to the velocity of the input steam jet. If the velocity of the input steam jet is high, it is necessary to increase the radius of the blades so that their tip velocity becomes correspondingly high. These long rotor blades subject the entire assembly to unmanageable mechanical stresses at high speed.

Parsons realized that he could, by using multiple rings of turbine blades on the same shaft, allow the steam to expand in stages through the turbine, and therefore extract energy more efficiently from the steam jet. This allowed him to utilize much lower jet velocities, of the order of 100 m/s, with correspondingly shorter turbine blades.

Parsons attacked the problem with characteristic gusto, so much so that by 1885 his first prototype was running successfully, giving 4.5 kW at 18,000 rpm. In 1889, frustrated by what he perceived as a lack of progress, he broke his partnership with Clarke Chapman and set up on his own in Heaton. He lost all his patent rights to the steam turbine; however, he was not daunted by this and simply developed a radial-flow machine that circumvented his own patents. In a radial-flow turbine, the steam expands outwards at right-angles to the rotational axis in contrast to the axial-flow machine where the steam expands along the length of the rotational axis.

Parsons realized that his invention was ideal for powering ships. Having received an unenthusiastic response from the admiralty, he set about proving his point in a characteristically irreverent manner. He built the Turbinia, a vessel powered by steam turbine and screw propellers. On the occasion of her diamond jubilee in 1897, Queen Victoria was reviewing the royal navy fleet at Spithead when Parsons appeared in the Turbiniaand raced through the fleet at the then unbelievable speed of 30 knots. The point was well made, and on November 21, 1899, HMS Viperhad her trials, reaching a speed of 32 knots.

Parsons was, first and foremost, a compulsive inventor. He spent his days inventing everything from children's toys to the Auxetophone, a mechanical amplifier for stringed musical instruments. His success as an inventor lies in his inquisitive nature and the fact that he was equally comfortable with theory and practice.

Parsons loved travel and the sea. It was on a cruise to the West Indies that he died aboard ship on February 11, 1931, in Kingston Harbor, Jamaica.

Bob Strunz