The Vaporising Problem
Sir Frank Whittle ensured that Britain entered the Jet age when, on 15 May 1941, the Gloster-Whittle E 28/39, propelled by of his jet engines, flew successfully from Cranwell, England.
The Shell Type Combustion Chamber adapted for use in the Whittle engine
Shell had played an important part in this milestone with its answer to the combustion problems that the original Whittle WU engine had been experiencing. The solution was the “Shell” combustion chamber. Sir Frank once said: “The introduction of the Shell system may be said to mark the point where combustion ceased to be an obstacle of development”.
During the engine’s development, Sir Frank had worried about combustion problems because he was aiming for a combustion intensity more than 24 times greater than any other of that time.
Although a design for a vaporiser combustion system had already been developed, it proved temperamental as its coils either blocked with carbon or burnt out. Such problems were a major obstacle in the further development of the engine.
The latest Rolls-Royce Trent 1000 next generation engine - the powerplant for the new Boeing 787
However, Isaac Lubbock, of the Shell Petroleum Company, was helping engineers from Power Jets – the Lutterworth company Sir Frank had formed to develop the turbojet engine – on combustion and fuel problems. Isaac invited the engineers to see a combustion chamber, similar to the size and form as the one being used in the engine. Shell engineers were also experimenting with the chamber in their laboratory in London.
The Gloster Meteor powered by the Rolls-Royce Welland engine, Britains first jet powered fighter in 1944
The fuel was being injected into the chamber in a fine mist of liquid droplets through a controllable atomising burner. A Power Jets team saw it working in the laboratory and were impressed. They took it to Lutterworth where it was set up for Sir Frank to see.
After that, they concentrated their effort on the “Shell” combustion chamber, which was adapted to the engine. Another Shell expert, R. Joyce provided further assistance, developing the burner.
A typical combustion chamber with vaporizer
Shell continues to research all aspects of jet fuel characteristics and performance at its research centre in Thornston, working closely with all major jet engine manufacturers.
Shell Aviation is marking the 100th anniversary of legendary British engineer Sir Frank Whittle, inventor of the jet engine, with a special brochure.
Copies of the commemorative leaflet, which explains the connection with Shell and the development of the Shell combustion chamber, are available for distribution to Shell Aviation customers and at events and trade shows.
We would like to thank Shell Aviation for permission to reproduce this article.