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).
Analysis of a manifold heating and fuel separation scheme for improving engine performance in cold weather.
| Identifier | ExFiles\Box 75\2\ scan0248 | |
| Date | 8th August 1921 guessed | |
| Oy2 - G 8821 Sheet #6. WHEN FLASK WAS USED TO COLLECT PETROL ONE DRAIN PIPE WAS CONNECTED Of course it would be possible to load up the two gas reservoirs by a number of starts and short runs in cold weather, but the reservoirs will be heated up very quickly, built round the exhaust pipes as they are, and even if they fill up we have no worse than a standard pipe and have only to run the engine say 15 minutes to empty them. In production the reservoirs would have removable plugs in the end so they could have any accumulated carbon cleaned out with a scratch brush. In this scheme it does not matter how much heat the fual receives, and indeed it is quite possible that carbonizing might take place on a long run, if the reservoirs got red hot, but since only a few drops of liquid get down into the pipes when the engine has warmed up, the accumulation of carbon should not be very rapid. There is no reason for any drop in horsepower since the air is not heated. Because of the time lag in applying heat, which is the essential defect of the hot spot scheme however elaborated, this seems quite a good line of development. 75% of cars which are run in the wintertime only run for 10 or 15 minutes on end in the cities, and then may stand in the open for hours, so that during the six cold months they may never get really warm enough to make a hot spot work effectively, and meantime a lot of liquid fuel has got down into the crankchamber. What may be called the "mechanical separation" scheme therefore has great possibilities. | ||