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 Harrison Radiator Division discussing various aspects of engine cooling systems.
| Identifier | ExFiles\Box 149a\3\ scan0223 | |
| Date | 9th September 1938 | |
| File 1278 HARRISON RADIATOR DIVISION GENERAL MOTORS CORPORATION LOCKPORT NEW YORK September 9, 1938 Mr. C. S. Steadman Rolls-Royce Limited Derby, Derbyshire England Dear Mr. Steadman: Please accept my belated apology for not answering heretofore your letter of April 27 which was enclosed with a copy of your paper on cooling systems, which has been gone over with care, particularly the way in which the breakdown air temperature is calculated as disclosed at the bottom of Page 8. With reference to fans in the second paragraph on Page 11, referring to other schemes put forward, etc., we have made experimentally over here a fan in which the angle of the blade is determined by the temperature of the air passing through the core; the difference in volume handled by the fan with the blades in the cold position as compared to the hot position at a fixed speed is twice the volume. However, cost is the factor which keeps this device off the market at this time. On Page 17, the second paragraph deals with the testing of bonnets for idling conditions, and in this connection we have found some few cases where the front vent was placed too close to the radiator, with the result that the fan pulled air through this vent, rather than through the core. This can be checked by use of silk streamers on a short rod; obviously, the streamers with the engine running should not enter the vent. On Page 20 you refer to unorthodox and likely future cooling system developments, and in this connection we have run and are running some cars with pressure systems, one in particular operating at 15 pounds per square inch, and we have operated systems with pressures as high as 25 pounds per square inch. One big problem we have run into is valve durability; however, we now have a circuit which we believe takes care of this matter quite satisfactorily. RADIATORS HEAT EXCHANGERS OIL TEMPERATURE REGULATORS THERMOSTATS HEATERS | ||