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).
The function and effects of Reatomizers versus vaporizer pipes in engines, particularly regarding fuel management and cold starts.
| Identifier | ExFiles\Box 75\2\ scan0281 | |
| Date | 2nd February 1922 guessed | |
| Oyl - G 2222 Sheet #3 with vaporizer pipes. We do not suppose that the use of 7 Reatomizers does away with the necessity of the vaporizer pipe, because we know that the latter is practically perfect in keeping wet fuel out of the cylinders (when the throttle is made to behave itself) and we feel that with the Reatomizers there would always be a certain amount of wet fuel in the cylinders after a cold start. But we may feel differently on this point after we have had an opportunity of thoroughly testing the Reatomizers. (We are shortly to receive trial sets, one set of which will be sent to you.) The effect of the Reatomizer in getting away with a cold engine is very remarkable on the American cars to which we have so far fitted it (Overland, Chevrolet and Buick). There is an entire absence of the stuttering and uncertainty of a cold engine which is characteristic of American cars and also of our own (bear in mind here that our American cars are left out in the open for 4 to 8 hours at a time in weather which is often 5° or 6° below zero). The principle upon which the Reatomizer works is that it scoops the liquid fuel off the wall of the pipe and throws it back into the middle of the air stream in the form of a finely divided emulsion which has every opportunity of properly evaporating and exists in such a finely divided form that it does not readily fall back on the wall of the pipe. is designed to The Reatomizer/create a minimum of obstruction in the pipe, because any obstruction causes an eddy which deposits liquid fuel on the wall by its centrifugal whirling action. We are told by the makers that when viewed through a glass manifold, a streak of white fog two or three inches long is seen flying horizontally from the end of each of the four chimneys of the Reatomizer and then disappearing in the air stream. We do know when a Reatomizer is fitted close to the throttle, some gasoline does get back on the walls of the pipe, but very much less than with no Reatomizer fitted. This I have proved to my own satisfaction on the Overland, in which the Reatomizer is close to the throttle, while the induction pipe beyond it is long and with several bends. The effect, therefore, of our 6 Reatomizers in the induction ports, which, of course, cannot affect distribution, is to blow the gasoline which hangs in the U tube of the induction bend into a fine spray and feed it into the cylinder continuously, instead of allowing it to accumulate in the bottom of the bend, and then feed it regularly to the cylinder in liquid slugs which cannot be digested by the cylinder.. | ||