Harry Ricardo was born in London in 1885, and was one of the first people in England to see an automobile when his grandfather purchased one in 1898. He was from a wealthy family and educated at Rugby. In 1903 he joined Trinity College, Cambridge as a civil engineering student.
In 1904, at the end of his first year, he decided to enter the University Automobile Club's event, which was a competition to design a machine that could travel the furthest on a quart of petrol. His engine was the heaviest entered, but his motorcycle design nevertheless won the competition. He was then convinced to join the Professor of Mechanism and Applied Mechanics, Bertram Hopkinson, graduating with a degree in 1906.
Upon graduation Ricardo set up his own company, the Two Stroke Engine Company, in order to sell a small engine and car he called the Dolphin. Although they had some sales, notably for fishing boats, the company nevertheless failed in 1911.
He set up a new company in 1915, Engine Patents Ltd, which developed the engine that would eventually be used in the first successful tank design, the British Mark V. A total of over 8000 of his tank engines were put into military service, making it the first British-designed engine to be produced in large numbers.
In 1917 Bertram Hopkinson invited him to join the new engine research facility at the Department of Military Aeronautics, later to become the RAE. In 1918 Hopkinson was killed while flying a Bristol Fighter and Ricardo took over his position. From that point on the department produced a string of experimental engines and research reports that constantly drove the British, and world, engine industry.
One of his first major research projects was on the problems of pre-ignition, known as knocking or pinging. To study the problem he built a unique variable-compression test engine. This led to the development of the octane rating system, and considerable investment into octane improving additives and refining systems. The dramatic reduction in fuel use as a result of higher octane fuel was directly responsible for allowing Alcock and Brown to fly the Atlantic in their Vickers Vimy bombers adapted with his modifications. The result of all of this work guarenteed England a supply of every-increasingly powerful fuels during the 1930s, which allowed their aircraft engines to outperform their German counterparts which ran on "natural" 87-octane fuel.
Another ate 20s-early 30s development was a new type of combustion chamber for diesel engines that allowed them to be run at high speed. The resulting design, known as the Comet, would go on to be used in a number of boats, trains, trucks as well as many World War II tank designs, including one of the same name.
Another major development effort was research into rotating-sleeve valve engines, which were widely used in the British airplane engine industry during the war. By the end of the war the Napier Sabre, based on his work, was the most powerful piston engine in the world at over 3,500hp. He was also instrumental in their decision to build a diesel-compound engine with extremely good fuel economy, the Napier Nomad, although it was not a commercial success. Bristol Engines and Rolls-Royce also developed powerful sleeve valve engines, the later's Rolls-Royce Crecy remained the most powerful engine of its size for many years after the war, at over 200bhp/litre.
After the war he opened Ricardo Consulting Engineers, which has become one of the most sought-after consulting firms worldwide. Almost every car company has at some time hired the firm for engine work, and most recently, transmission design.
During the 1960s a second round of development of the Comet system was started, now armed with considerably more powerful test apperatus. The refined design was immediately used in several cars, and the general pre-combustion system remains in use in most diesel engines today. Ricardo Consulting remains commited to the diesel, considering it to be nowhere near its development potential even in the most advanced of today's engines.
In 1978 the US Department of Energy hired Ricardo to research the Stirling engine as a car engine. A series of engines, eventually 45, were built to test this system and showed very low emissions, but the efficiency was compromised by the need to operate under transient conditions -- the design was best running at a single speed, making it less than useful as a car engine. The Stirling may make an excellent engine for hybrid cars and has recently generated some interest in this role.
In 1986, the Rutan Voyager was the first aircraft to fly around the world non-stop and without refuelling. Ricardo Consulting redesigned the otherwise "stock" Teledyne Continental engine to incorporate a highly efficient combustion system and water cooling, thereby dramtically reducing drag and improving fuel economy.
Ricardo had long worked on direct injection gasoline engines as well as diesel, work that finally started to come o fruition in the 1990s. Today several stratified charge engines are in use in the automobile market, designs that would not have existed without his constant work on them.
Recardo was elected Fellow of the Royal Society in 1929, and in 1948 was knighted. He died in 1974 at the age of 89.
External links
Sir Ricardo’s Description of Combustion in Diesel Engines