Sir Harry (Ralph) Ricardo - Engines

Mechanical engineer, born in London, UK. He studied at Cambridge, where he designed and built several small petrol engines, and began to work on the problems of ignition, combustion, and detonation. He soon recognized the importance of the type of fuel in avoiding detonation or ‘knocking’, and this led to the use of octane numbers to measure the anti-knock properties of petrols. His improved design of the combustion chamber in side-valve engines has been universally adopted.

Sir Harry Ricardo (1885-1974) was one of the foremost engine designers and researchers in the early years of the development of the internal combustion engine.

He patented the two-stroke engine design, personally developed the engines that would be 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 pre-combustion chamber that made high-speed diesel engines possible.

Harry Ricardo was born in London in 1885, descended from a brother of the famous political economist David Ricardo.

Engines

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 (1 L) of petrol. His engine was the heaviest entered, but his motorcycle design nevertheless won the competition.

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.

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. From that point on the department produced a string of experimental engines and research reports that constantly drove the British, and world, engine industry.

Another late 20s-early 30s development was a new type of combustion chamber for diesel engines that allowed them to be run at high speed.

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 3,500 hp (2,600 kW). He was also instrumental in Napier's 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 latter's Rolls-Royce Crecy remained the most powerful engine of its size for many years after the war, at over 200 bhp/litre (150 kW/L). The refined design was immediately used in several cars, and the pre-combustion system remains in use in most diesel engines today. Ricardo Consulting remains committed 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 Consulting to research the Stirling engine as a car engine. A series of engines, eventually forty-five in total, 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. Ricardo Consulting redesigned the otherwise "stock" Teledyne Continental engine to incorporate a highly efficient combustion system and water cooling, thereby dramatically 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 to 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.