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).
Letter from Ethyl Export Corporation discussing engine detonation and quoting German research papers.
| Identifier | ExFiles\Box 27a\4\ Scan179 | |
| Date | 25th July 1933 | |
| CABLEGRAMS: ETHYLPORT, LONDON. TELEGRAMS: ETHYLPORT, CHURTON. ETHYL EXPORT CORPORATION Incorporated in the State of Delaware, U.S.A. with limited liability. ABFORD HOUSE, VICTORIA LONDON, S.W.1 Telephone: VICTORIA 5520 Head Office: 135 EAST 42ND STREET NEW YORK, U.S.A 25th July, 1933. A.{Mr Adams} C. Lovesey Esq., Experimental Dept., Rolls Royce Ltd., Nightingale Road, DERBY. Dear Lovesey, You may know that we have had a World Petroleum Congress on in London for the last week. There have been several papers which I think would have interested you, but I myself have not had time to go into them thoroughly. However, I notice a paragraph in one of the German papers by Dr. von Philippovich, who is one of the D.V.L. people, which I think will be of particular interest to yourselves. I am quoting the paragraph as it is given in the summary on Dr. Philippovich's paper. "Special types of indicator have also been developed for studying "detonation. Temperature measurements taken at as many as 30 points in "a liquid-cooled aero-engine cylinder at the D.V.L. have shown that with "glycol at 82°C the excess surface temperature was double that found when "water at 80°C was used as the cooling medium. With rising jacket "temperature the difference diminished and with glycol at 145°C the "cylinder surface temperature was the same as that with water at 80°C". With reference to the curves you gave me the other day and your query regarding the relative effects of mixture temperature and/or cylinder temperature on power, I think that it is generally agreed that the mixture temperature has a greater effect on the power output and the tendency to knock than the jacket temperature. I give you below extracts from a paper read at the Congress entitled "Effect of Engine Design on Octane Number Ratings". "As shown in Table II (Part A) decreasing the temperature of the charge "(gasoline-air mixture) entering the cylinder from 300 to 100°F resulted "in a 35% increase in power output and an increase of four octane numbers "in the rating of a cracked gasoline. The increase in rating is due to "the lower combustion-chamber temperature. The increase in power output "is due to a combination of a lessened tendency to detonate, higher "permissible compression pressure, and greater weight of charge entering | ||