From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Page from an invention specification detailing a combustion chamber design to reduce detonation.
| Identifier | ExFiles\Box 147\2\ scan0178 | |
| Date | 21th December 1939 guessed | |
| under the said projecting portions of the cylinder head. I do not wish to commit myself to the theory that it is the localisation of the detonation wave as aforesaid which secures the benefit of this invention but I have found that by so form- ing the combustion chamber advantages are secured and that using a fuel which would be suitable with a flat top piston and, for instance a 6 : 1 compression ratio, the compression ratio can be raised to a figure in the neighbourhood of 8 : 1 without increase of intensity of detonation. Preferably the walls of the combustion chamber where these spring from the said projecting portions of the head and the walls of the said projection adjacent to such last mentioned walls are both normal or substantially normal to the said projecting portions of the head and these two sets of walls lie close together so as to leave a comparatively small space between them. Preferably the top of the said protuberance is in a plane at right angles or at an angle less than a right angle to the last mentioned walls of the protuberance. Where part of the combustion chamber lies to one side of 3. | ||