Harry Ricardo

Sir Harry Ralph Ricardo (26 January 1885 – 18 May 1974) was an English engineer who was one of the foremost engine designers and researchers in the early years of the development of the internal combustion engine.

Among his many other works, he improved the engines that were used in the first tanks, oversaw the research into the physics of internal combustion that led to the use of octane ratings, was instrumental in development of the sleeve valve engine design, and invented the Diesel "Comet" Swirl chamber that made high-speed diesel engines economically feasible.

Early life

Harry Ricardo was born at 13 Bedford Square, London, in 1885, the eldest of three children, and only son of Halsey Ricardo, the architect, and his wife Catherine Jane, daughter of Sir Alexander Meadows Rendel, a civil engineer. Ricardo was descended from a brother of the famous political economist David Ricardo, a Sephardi Jew of Portuguese origin. He was one of the first people in England to see an automobile when his grandfather purchased one in 1898. He was from a relatively wealthy family and educated at Rugby School. In October 1903 he matriculated at Trinity College, Cambridge as a civil engineering student. Ricardo had been using tools and building engines since the age of ten.

Marriage

In 1911 Ricardo married Beatrice Bertha Hale, an art student at the Slade School of Art, in London. Her father, Charles Bowdich Hale, was the Ricardos' family doctor. They had three daughters, and lived most of their married life at Lancing and Edburton in West Sussex.

Car engines

In 1904, at the end of his first year at Cambridge, Ricardo decided to enter the University Automobile Club's event, which was a competition to design a machine that could travel the furthest on 1 imp qt (1.14 l) of petrol. His engine had a single cylinder, and was the heaviest entered, but his motorcycle design won the competition, having covered a distance of 40 miles (64 km). He was then persuaded to join Bertram Hopkinson, Professor of Mechanism and Applied Mechanics, researching engine performance. He graduated in 1906 and spent another year researching at Cambridge.

Ricardo is said by Percy Kidner, then co-managing director of Vauxhall, to have had a hand in the design of the Vauxhall engine designed by Laurence Pomeroy for the RAC 2,000 miles (3,200 km) trial of 1908.

Before graduation, Ricardo had designed a two-stroke motorcycle engine to study the effect of mixture strength upon the combustion process. When he graduated, the small firm of Messrs Lloyd and Plaister expressed interest in making the engine. Ricardo produced designs for two sizes, and the smaller one sold about 50 engines until 1914, when the war halted production.

In 1909 Ricardo designed a two-stroke 3.3-litre engine for his cousin Ralph Ricardo, who had established a small car manufacturing company, "Two Stroke Engine Company", at Shoreham-by-Sea. The engine was to be used in the Dolphin car.[6] The cars were well made, but they cost more to make than the selling price. The company fared better making two-stroke engines for fishing boats. In 1911 the firm collapsed and Ralph departed for India. Ricardo continued to design engines for small electric lighting sets; these were produced by two companies until 1914.

Tank engines

In 1915 Ricardo set up a new company, "Engine Patents Ltd.", which developed the engine that would eventually be used in the first successful tank design, the British Mark V. The Daimler sleeve-valve engine used in the Mark I created copious amounts of smoke, which easily gave away its position. Ricardo was asked to look at the problem of reducing smoky exhaust gases and decided that a new engine was needed - despite the constraint that any new design would have to fit into the same space as the existing one. Existing companies were able to undertake construction of such an engine but not the design, so Ricardo designed it himself. As well as having reduced smoke emissions, the new engine was much more powerful than the existing ones. The new six-cylinder engine produced 150 hp (110 kW), compared with 105 hp (78 kW), and later modifications produced 225 hp (168 kW) and 260 hp (190 kW) By April 1917 one hundred engines were being produced a week. A total of over 8,000 of his tank engines were put into military service. The Mark IX tank, as well as the British version of the Mark VIII, also used a Ricardo engine. In addition to being fitted to tanks, several hundred of the 150 hp (110 kW) engines were used in France for providing power and light to base workshops, hospitals, camps, etc.