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).
Challenges and future development directions for compression ignition engines.
| Identifier | ExFiles\Box 179\1\ img118 | |
| Date | 25th November 1931 | |
| Sgd. FROM R.{Sir Henry Royce} ORIGINAL C. to WGR. RG.{Mr Rowledge} HS.{Lord Ernest Hives - Chair} BX. XU 433 COMPRESSION IGNITION ENGINES. The trouble with compression ignition engines is that unless the speed and M.E.P. is high they are too heavy. The long stroke engine which is necessary to get a reasonable combustion chamber does not allow large enough valves in the head for high volumetric efficiency at high speed, hence the M.E.P. is low at high speed. So that as matters stand we must have either 2 cycle or sleeve valves, or we can have 2 cycle and moderate speeds, and use pistons as large area inlets, and exhaust by grouping 3 or 4 small valves in the head, as suggested by me 2 or 3 years ago. We can supercharge our present unit and so get more air into the present cylinder, or we can use sleeve valve 4 cycle or 2 cycle, and endeavour to overcome the natural trouble of the latter (gummed rings.) But at present we are nearly at a standstill fretting at the bit. There is no doubt that compression ignition is coming for aero work, and is needed for safety in the air both for travel and war work. R.R. is willing and anxious to do something at once in accordance with the Air Ministry's wishes, and are even willing to risk some of their own money and get some alternative to the work as directed by the Air Ministry, in parallel with Air Ministry work, not neglecting carrying on to their instructions. Personally I will meet Mr. Pyre and Mr. Tweedie next week, here, or in London, with RG.{Mr Rowledge}, E.{Mr Elliott - Chief Engineer}, and HS.{Lord Ernest Hives - Chair}, to fix up a programme. R.{Sir Henry Royce} | ||